macuahuitlgog: It's a shame, there is no real way to back up your Steam games.
sharp299: And there is another big problem, there are people whose libraries have more than 1000 games, How would they do to download them all in such a short time?, And still do a backup of them, there are games like wolfensten the new order weighs around 40 gb. : /
You may already be aware of this, but for GOG there's
gogrepo.py.
For huge games, I guess one would just have to prioritize level of importance.
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On the topic of DotEmu's SEGA game emulations, the controls feel delayed or off or something (like hard to control mid-air when jumping, in Kid Chameleon); I guess that's par the course for DotEmu since many others have complained about this issue with their games, iirc.