Having gone through the game again, I have now come up with a comprehensive final timeline for the ENTIRE BTTF franchise, including the movies AND the Game.
This timeline includes events which DEFINITELY occured (or were likely to have occured) in the final timeline as of the end of Episode 5. Events in alternate timelines/erased timelines in the movies and the game, aren't included (though, if time travelers arrived from those timelines, then they will be mentioned). I will also not really focus much on the time traveler's memories, and which timeline they are originating from, unless such info is necessary to understand the timeline.
Anyways, here goes-
-Sometime in May or June of this year (possibly earlier), Edna Strickland arrives from 1931 in a stolen Delorean and makes a nuisance of herself in Hill Valley, earning the ire of Beauregard Tannen.
-July 17th-Edna attempts to burn down Tannen's tavern. Marty and Doc arrive (from the alternate 'Burnt Hill Valley' 1931) in their Delorean and prevent her from doing so. After a chase, they forcibly transport Edna and her Delorean back to 1931.
-January 1st-Doc arrives from 1955, and discovers that the lightining has disabled the Delorean. He spends the next 8 months as a blacksmith, attempting to repair the damage, while earning the ire of Bufford Tannen.
-September 1st-Doc has buried the Delorean in the Delgado Mine and sends a letter to Marty through Western Union.
-September 2nd-Marty arrives in 1885, from 1955.
-September 3rd-Marty and Doc meet up and Marty warns Doc of his impending death at Tannen's hands, showing him the photograph of the tombstone.
-September 4th-Doc saves Clara and falls in love with her
-September 5th-At the Town Festival, Marty saves Doc from being shot by Bufford. They take a photograph at the inaugration of the Clock Tower.
-September 6th-Doc tells Clara he is a time travel; he gets drunk
-September 7th-Marty faces off against Bufford and defeats him. Marty then returns to 1985 while Doc and Clara stay behind.
-At some point, Shonash Ravine is renamed Eastwood Ravine.
-Doc and Clara get married and have two children, Jules and Verne.
-By around 1895, Doc completes the train time machine, and returns to the future, with his family. Eventually, he decides to relocate the family to the 1980's altogether, owing to his desire to return to managing his late father's foundation.
-At some point in May or early June, Doc (from the 'original' timeline as off the end of BTTF3) arrives in 1931 and assumes the identity of 'Carl Sagan'. His intent is presumably to discover the truth about Marty's grandmother Sylvia, for the book he's writing on the McFly family, but he gets sidetracked by the mystery of the speakeasy fire. He is framed by Edna, and arrested. Einstien gets into the Delorean after stealing Edna's shoe, and the auto-retrieval feature sends him and the car back to 1986.
-Presumably, the Doc of the final timeline ALSO arrives at some point in another Delorean, with a similar motive vis a vi Marty's grandmother, but doesn't get sidetracked by the speakeasy fire, since in his timeline, it was never a mystery. He safely returns to 1986.
-June 13th-Marty arrives from 1986 and enlists the aid of teenage Emmett Brown to break Original Doc/'Carl Sagan' out of jail. While he and Emmett work on the rocket drill, a SECOND Marty arrives from later that day to rescue his grandfather, Arthur McFly, from Kid Tannen's goons. The first Marty succeeds in breaking Doc out of jail before Kid Tannen kills him, and the second Marty succeeds in saving Arthur. The first Marty decides to travel back a few hours, possibly to retrieve Einstien, since he and Doc realise that Einstien is missing. When this Marty travels back, he is replaced by the version of Marty who remembers reading the newspaper article about Arthur McFly being beaten to death. Marty and Doc then use the Delorean to return to 1986, after telling Arthur to go into hiding.
-August 25th-Marty and Doc arrive from an alternate 1986 (ruled by Kid Tannen) and set about manipulating events to ensure that Kid Tannen is brought to justice. In the process, young Emmett falls in love with Edna Strickland and does not see Frankenstien. Marty and Doc return to 1986, and Original Doc and Einstien are erased from existence at this point, as they are shunted into the alternate timeline of 'Citizen Brown'.
-October 12th-Marty and Citizen Brown arrive from the alternate 1986. Marty attempts to break up Emmett and Edna's relationship and succeeds, while FCB is trying to destroy his younger self's interest in science.
-October 13th-Marty succeeds in ensuring that young Emmett's experiment at the Expo is a success. His arbitration leads to a much better relationship between Emmett and his father. FCB is erased from existence, and Edna steals the Delorean. Doc (of the final timeline) arrives in 1931, having seen the newspaper clipping he received from Marty as young Emmett. Edna travels back to 1931 and Marty and Doc fade from existence (because they have been shunted into an alternate 1931). Later that night, Marty, Doc and Edna all return and Edna's Delorean (the Delorean of the Original Doc) is erased. Marty learns that Trixie Trotter is actually his grandmother Sylvia. Marty and Doc then return to the future. Edna is imprisoned, along with Kid Tannen.
-George McFly is born to Arthur and Sylvia in 1938. Biff is also born, to Kid Tannen and an unknown woman.
-At some point, Edna and Kid Tannen fall in love, while in prison together.
-Judge Brown dies...owing to the close relationship between them, Emmett runs a Foundation in his memory. Emmett also fully establishes himself as a scientist.
-November 5th-Marty arrives from 1985, and prevents the first meeting between his parents (as it happened in his timeline). He meets Doc. Doc may or may not recognise him as the Marty he'd met back in 1931. In any case, Doc discovers that he built the time machine in 1985. He devises the plan to send Marty back to the future.
-Marty spends the week trying to get his parents together.
-November 8th-Biff Tannen crashes into the manure truck.
-November 12th-Early in the morning, a second Marty and Doc arrive from the alternate 'Hell Valley' 1985 to prevent young Biff from getting the Almanac. Old Biff arrives later in the day and gives young Biff the Almanac. The first Marty tries to get his parents together at the dance, while the second Marty tries to get the book from Biff. George and Lorraine fall in love, ensuring Marty's existence. The second Marty gets the book from Biff but it is stolen back. Marty succeeds in stealing the Almanac back from Biff and burning it. '85 Doc however, is struck by lightning and sent back to 1885 (while a temporal duplicate of the Delorean is sent to 2025). Marty receives the letter from Western Union. In the meantime, '55 Doc sends the first Marty back to the future and faints on seeing the second Marty.
-November 13th-14th-Marty tells Doc about his older self being trapped in the past. They uncover the Delorean buried in the Delgado Mine. Marty goes to the library to look up Doc's fate and discovers the photo of him and Doc by the Clocktower taken in 1885.
-November 16th-Having realised that he was 'meant' to go back to 1885, Marty travels back in the repaired Delorean. When he travels back, he is replaced by the version of Marty who remembered seeing Doc's tombstone in 1955.
-Doc spends the next thirty years constructing the Delorean, though he presumably now has a head-start, having rebuilt the time circuits already in 1955. In 1962, the Brown Mansion burns down, and Doc moves into his garage. He wins a civic award in 1983.
-At some point, Doc pieces together and reads the letter Marty gave him in 1955 about his impending death at the hands of the Libyans.
-Sometime in the 1980's, Marty meets Doc for the first time (from his POV). Doc of course knows this is the same Marty from 1955 but he may or may not have guessed this is his old friend from 1931.
-Kid Tannen and Edna may have gotten married in this period...both having reformed. Edna is now on friendly terms with her ex-boyfriend Emmett Brown.
-October 26th-Doc carries out the first temporal experiment at Lone Pine Mall. The Libyans attack, but Doc survives thanks to his bulletproof vest. Marty travels back to 1955 accidentally. The 'second' Marty, who arrived from 1955 ten minutes earlier, rushes to the mall to discover that Doc is alive. Doc then takes the Delorean and travels to 2015. The next morning, Doc returns from 2015 and takes Marty and Jennifer to the future.
-October 27th-Early in the morning, Jennifer fades INTO existence on her porch, having been phased back into the normal timeline when the alternate 'Hell Valley' timeline was erased. Ditto for Einstien. At 11 am, Marty arrives from 1885 and the Delorean is destroyed. Marty chooses NOT to race Needles, thus erasing his bad future. Doc, Clara and the kids arrive in the train to visit Marty and Jennifer, and then leave.
-At some point, Doc, Clara and the kids settle down in 1986 for good. They presumably purchase another house, though Doc still maintains the lab for experimental purposes. Doc continues to run his father's foundation.
-May 14th-While Marty is hanging out at the Brown's garage sale, Original Doc's Delorean arrives owing to the auto retrieval feature. Using Edna's shoe, Marty tracks down Edna and reads the newspaper article about 'Carl Sagan' escaping from jail. Realising that SOME version of Doc is in trouble, Marty travels back to 1931. When he does so, he is replaced by the version of Marty who read about Carl Sagan being shot dead, and more importantly, who is from a timeline where Doc DIDN'T return to the 1980's.
-While at the Key to the City ceremony, final timeline Doc reads the newspaper clipping his old friend Marty had given him back in 1931. Realising that both Marty's are one and the same, Doc travels back to the day of the Expo in his Delorean to pick up Marty.
-May 15th-Marty and Doc return from 1931, and are almost immediately confronted by the conundrum of three alternate Marty's from the future!
-Doc, Clara and the kids arrive from 1885 in the time train. Doc has the train hover-converted. After learning about Marty's improved future, they travel back to 1985 to meet teenage Marty and retrieve Einstien.
-On one of his travels in the time train, Doc discovers the temporal duplicate of the Delorean created when lightining struck it in 1955. After making necessary repair/upgrades, including the auto retrieval feature, Doc takes the Delorean back with him to 1986 and uses it for further time travels.