Nifty question, huh ???????????????????
Hmmmm....
I am not familiar with the latest latest latest version of MMJ as I only had it installed for about 5 minutes last week and then removed it for other reasons !!!
The one thought I have for starters is to ask, if when you select the 'Add' function, are the 'correct' file types/extensions 'allowed for' in the search for your music files ?
(I cannot recall if that option - file extensions - is applied now in MMJ !)
Last for now... I would always strongly recommend to users to create a
Music BANK folder where all of the music is saved... Make copies of what you wish to share to your sharing folder(s)... Use the 'bank' for your play-list selections and such...
Of course this assumes that you have enough Hard Disk Space !
Protect your music files and copy the files you want to share or edit or re-tag or whatever... It's too easy today for too many people to lose years of music files simply from one wrong click... Well, at least 2 wrong clicks, ha ha ha...
The main point of this is that your successfully downloaded files should NOT be 'stored' in any folder(s) directly related to LimeWire (or any other p2p client).
Create your own personal folder(s) for storing your files.