I was playing it when they broke my modded game, and I had to mod it, to even play, Steam sold it broken for W7+, and this was before refunds existed
The unannounced update, trashed my game, and on that day you could only have the TSLRCM+planet mod(s), no other mods were compatible.
Then whem mods were made compatible, it was found you could only have one, as they'd only bothered about getting TSLRCM+Planet working, and all to sell Big Picture mode/SteamOS, not benefit existing owners..
I expect an update fixed it, but by then, I had the GOG versions, and I'm sure most original mods never got added to the Workshop.
I'd rather have 10 years of mods to use, than a controller, I never use one now, and I used to be a console gamer.
Took me a while to get used to K&M, but when I did, I never went back.
I don't know why you'd want to use a controller, with an RPG, due to limited options, but your issue was loooking for a game specific mod, when multi-game tools are already available, like these.
This one lets you try it first.
JoyToKey is a shareware and license key (price = $7.00 USD) needs to be purchased for continued use. JoyToKey - Download the Latest Official Version
Xpadder is only 9.99 USD Xpadder
is an old one, I tried years ago, it still around.
Controller Companion $3.00 USD or more (+ VAT), also on Steam Controller Companion
I'm sure a free one exits, if you look in the right place, but if you have to use a controller, these prices are low enough.