Hmm, odd. Here's one possibility:
Often when attachments are posted on forums, all spaces are converted into underscores. LFS looks of the exact car name to display the appropriate setups, if there's an underscore instead of a space, it won't display it. So just change "FORUMLA_XR" to "FORMULA XR" (for example) and that will make such setups appear.
If that's not the problem, I've really no idea.