Trying to use this mod https://diablopat.ch/index.php for a near 100% vanilla experience with single player difficulty selection and item highlight -- all other mods add more than that. In any case, I get a hash error when trying to run the patch with this game. Any reason it shouldn't work when it specifically states it just needs 1.09?

not sure why, maybe small version difference.

i would suggest using Torch mod instead, it works for GOG's Diablo and on Bnet, use the Windows 10 version.

https://freshmeat-blog.de.tl/Diablo-Torch.htm

Because GOG Diablo runs on 1.09 v2 instead of 1.09.

first release of GOG was already not working with DiabloPatch, its website clearly states only works for 1.09. but no one knows why 1.09b won't work since from 1.09 to 1.09b (the old official patch) only fixes a sound problem for Windows NT 4.

svfn and realposojed, you both used past tense 'was not working' 'couldn't work' ... does this mean GOG updated Diablo with a 1.09"a" version that is compatible with DiabloPatchMod?

Also, Torch has a lot of extra non-vanilla features I don't want (though it seems they can be disabled) but it does not mention singleplayer difficult selection which is pretty important for me.

no, it never worked for me, even if it did, i still prefer Torch / StrangeBytes ddraw prior to GOG release. the only QoL i missed is shift clicking potions to belt, i also have Hellfire so i can select difficulty for SP. Hellfire is the easiest way to get that difficulty selector without other extra mods.

GOG's first version was already 1.09b and the mod says it only works for 1.09 so it's up to the modder to correct or update it if there is an issue.

yeah Torch does not include SP difficulty selecting.