Some times Gnucleus forgets to put the trailing bracket in a file name (partial) and then won't see the file in the partial directory.

Easy fix is to manually insert the closing bracket.

Example:

santana - maria_maria (5247272,santana maria mp3.mp3

fix by renameing,

santana - maria_maria (5247272,santana maria mp3).mp3

note the second bracket.

only a minor problem but might be an easy bug fix.