OK I figured it out. Seems to be the case whenever I post an issue I fix it almost right after.

Turns out its due to the same issue Clip Studio Paint has with their zoom bug after the Windows Creators Update.

What fixed their bug and this ArtRage bug, is setting Windows Text Scaling to any value above 100% (101% for example).

Doh.

Still, this means its an ArtRage bug?