<pardon the late response>
Thank you for the offer of a refund but, to be honest, I can't say I really want one. I don't know, maybe that's just me.
I must thank you for trying to help me though; this is a very odd bug I've managed to encounter. But, I understand this is difficult to fix, let alone pinpoint. So, I guess I'll just have to leave it now.
Consider this case closed.