It is compatible with Win 10. In the unlikely even you have any issues, try the
Windows 8 Performance "Patch" (works in Win 7 and 10, as well).
It is kind of the most up to date. There were issues with some of the backups when the download version was released on Steam, so some of the later fixes and changes are included, and some not (ie you can not finish Finnigan's quest and then buy back the lockpicks for 20 gold, but that was silly, anyway). The higher resolution support and compatibility fixes were re-added to the best available code.
Check your PM.