This may seem trivial and I hate to bring up Steam, but Valve never did fix the annoying thing whereby the client never starts up in maximum mode, which sometimes results in clicking and moving the client outside the window. With Gog it is a little different in that it always starts in a set window size, but damn I'd love for it to remember my maximise option and launch that way. Forcing it doesn't work, just like with the Steam client.

:'( It make me sad.