Yes, what i did was install 3.6 first and then just copy/paste the mod from my other PC - back then i just played custom battles between the computers which worked just fine. But the campaign crashes when about to enter it, and this was not the case on the other compute when i last played a campaign last year in july. I don't think i have made any changes affecting the campaign since then.
I am going to try and move the mod to my win 7 older computer- as i have two older computers. And see if it works there. If not, i may need to re-work everything onto the unofficial 4.0 version which actually has a working campaign. But that would take some time as i did not only add units but also replaced some who were already in the mod. The norse_swordsmen weren't removed but simply replaced with the Berserkers of WotN. Will be annoying to do all that but if that would work i'd get the changes from the unofficial patch as a bonus.
Yes, other mods work fine and other versions of TLK.