So I've already gotten 100% achievement completion on this game though Steam and I've noticed that all of my settings and almost all of my achievement progress was carried over to the GOG version.

The issue with this is that a lot of achievements that I have yet to unlock through GOG Galaxy are already showing up as being unlocked in-game and are no longer being tracked, which I suspect would be the cause for me not being able to unlock the 'Kill It With Fire' achievement for killing 30 arachnoids with the Incinerator, because I've technically already accumulated 30 arachnoids kills with the achievement progress that I already have.

Is there any way that I could reset my in-game achievement progress to try and fix this bug, or are there any other solutions to this?
I should clarify that this topic was in reference to the"Kill it With Fire" achievement for DOOM + DOOM II.

Sorry, I thought I uploading this topic to a dedicated forum for this game. I'm completely new to using the GOG community fourms.

I've just tried this and it only seems to be affecting my in-game save files, my achievement progress is uneffected and I presume is being linked through my Bethesda.net account. I'll submit a support ticket to Bethesda about this and see what they say about it. I'll give this a try too. I appreciate the help!