Hi, I'm experiencing the same kind of problem.
I purchased the entire first season of SAM & MAX (Dec 31, 2007) and can't activate the product. Some forums say that the downloads should be SELF activated, but no matter where I download the file from, (findmyorder or telltale) I STILL get the screen asking me to enter an order number and password!
I uninstalled, reinstalled, and it's NOT allowing me to play the full game!
I've already e-mailed firstname.lastname@example.org
on Dec 31. Are you guys on vacation?