Sup sup ppl.
First of all, this fix is mainly for windows 7
(might work for vista also) works for windows vista too.
1st: Run Steam as administrator.
2nd: Add c-rpg launcher as non-steam game.
How to add c-rpg as a non-steam game for those who haven't read the devs suggestion for this problem:
Btw you missed a step if you want to get the steam overlay.
1 ) Run steam as administrator
2 ) Add the cRPG-Launcher as a non-steam game
3 ) Create an desktop icon of the added cRPG-Launcher from your steam library.
4 ) Always start your cRPG per created desktop icon from your steam library.
5 ) Enjoy your Overlay )
I dunno if you just forgot to add the third step and it still didn't work as I described.
Now for some of you this ends here. But some the Steam overlay won't still work, for those here's the problem (or at least for me it was):
UAC (User Account Control). Steam doesn't seem to like this when it comes to non-steam games. So basically you just need to disable it.
3rd: Disable UAC.
You can either google how to disable it, or you can just run any program as administrator and when the UAC pops up, there's little box where it says something like "control when to show this message". From there you can disable it.
If you choose/need to disable your UAC, every time when you install a new program from web or generally have downloaded something, before opening it right click it and choose the option where your firewall will check it for viruses and stuff like that (You should do this even if you're using UAC). This feature might not be able for every firewall though.
You still should be at least little bit sceptical when doing this, as it won't notice you anymore when you're changing windows or installing some new programs. Once devs fix the issue I recommend you to turn this back on.
EDIT: If this doesn't fix it, I might still be able to help you fix it so feel free to pm me.