Some files are licenced and unuseable, It is generally advised that you should not download Programmes off Limewire. They are often trial versions ... incomplete, filled with viruses and unusable. Wmv video files are equally not advised. If you tell us what TYPE of file you have problems with we can help more possibly, but absolutely no file names on the forum pease.
And no you cannot usually find out before download although right clicking in the search window>advanced>Bitzi look up will often give you useful information on the file. That feature opens your browser and takes you to a page for the file on the Bitzi site.
I hope this helps a bit
