Got a lua error about Interface/AddOns/Details/core/parser.lua:2438: attempt to index global 'LIB_OPEN_RAID_BLOODLUST' (a nil value)

No idea about coding but I'm guessing the addon was trying to get bloodlust code to work in classic when the spell doesn't exist. I deleted the line of code in the lua file and that seemed to fix it right away, so I'm guessing it's some leftover code not meant to be there or something.

You installed the incorrect version for era. The (classic) entry on CF is the one you want

Both the (classic) version and the other version showed up in curseforge while in the classic addon section(not the wotlk section). And details didn't seem to work properly for me without having both installed for some reason either, that's why I have both of them. It seems to work just fine after deleting that one piece of code

You absolutely should not have both installed. Uninstall both and install only the (classic) entry. I will try to spend some time soon actually adding support for era in the regular addon.

Ok, got just details classic going now. Reason I had both was because there was some visual bugs on the windows in the classic version, green texts over the icons at the top of the window and the whole window being too dark/greyed out. Deleting the windows and making some new ones fixed it for now. Might want to make sure the non classic version is not in the classic tab for curseforge, I'm probably not the only one that thinks they might need both.