There is a known issue with .wav files that are created on PC's are grayed out when you attempt to import these files. There is a utility included with Deck LE and Deck 3.5.3 that allows the file type to be modified for import. You may download it here:
www.frederikseiffert.de

By selecting the .wav files you wish to import into Deck and changing the File Type to "WAVE" - without quotes - you will be able to then import the files into Deck. If you have several .wav files you wish to import, you can select multiple files and change their types in one step using File Type.