Yes there is a way to fix it. You need a renaming utility program first. I use Bulk Rename Utility.
http://www.bulkrenameutility.co.uk/Main_Intro.phpJSGME saves backups of your original files that it replaces. In the MODS folder there is !BACKUP folder. Each file has an added extension with the name of the mod you enabled added. EX) crowd.iff.UBR mod where 'crowd.iff' is the original file name and 'UBR mod' is the added extension. You need to remove the added extension. I would make a temporary copy of the !BACKUP folder and work on that. Using a renaming program remove the added extension. Bulk Rename Utility allows you to remove characters. You need to remove the "last n" characters. I don't know which options you need (trim, chars) or maybe the extensions sections is better. I think it can remove a certain number of characters. Try this on a temporary folder so you don't mess up. You have to read the help section if needed. You do have to option of doing this manually for more than 4,500 files.
If JGSME says the mod is installed, disabling may fix the problem. Check the number of files in the UBR mod folder and the !BACKUP folder. If they match the mod installed correctly. If not use the renaming method. Do not try to enable the mod again until you have all the files reverted back to normal. Otherwise you can screw up the default files by mixing them with UBR files.