I bought an album where the file-name in one track was 189 characters (maybe I have missed some characters). This file couldn't be imported to Sooloos.
I shortened the file name (around 20 characters) and the it was possible to import the track. Anyone who knows the limit of the file-name?

861v8+ID41, HD621, G98, Arcam P35, DSP7200SE, DSP7200HC, SW1600, DSP320.
2xMS600, 2xMS200, 2xDSP3200, AC200, Explorer2, 2x218, AD88, Prime, 251