As in the title which one? I have had it for a few years now and just went back to it( had to use the game seach function on the site).
I want to use some mods but do not know which mods will/ or won't work due to its Versiom.

I know it is older in that the bath house scene is still nude for the NPC's

Complete edition or GOTY edition?
Anyway, the game is currently 1.32 patch, but mods for 1.31 patch can work.

It calls itself as the complete edition as in the title. I know it is an older version as the Bathhouse segment is in full nudity for the female NPCs (no mods used for it) whereas another version I have seen on you tube is covered in towels.
Also I cannot use the verify/repair function as it is grayed out.

I have tried 2 1.31 mods( infinite weigh and unbreakable boats) and no go. Do I have to make a mod folder and put them in there?

still don't know vesrion number but I found my old game old back ups that contain mods I used on one of my drives.
I made a mods folder for this iteration and moved the backups and 2 newer mods into it and they are working.