I dont think you can but it's time to realize that GOG is an eminent player in gaming world and it's here to stay and I think supporting GOG versions will only bring more and more members, just my two cents..
For what it's worth to the powers that be, I totally agree with you.
I very rarely buy games from Steam. I like actually "having" the games wherever and whenever I want them and that means buying them mostly from GOG.
If anybody else out there agrees with this, please let CH know. We need trainers that work with GOG versions of games as well as Steam versions.
That would be fair if you charged double the credits for Steam trainers as well. Is that what you are going to do?
There's one other thing I forgot to mention in my last message.
If I had been told from the beginning that GOG trainers would be virtually nil then I would not have joined CH. After all, if you want your members to be fair by paying double (in price or credits) then you should be fair about being clear and up front as to whether or not we'll get the trainers we need and request.