With the uTool, you can import/export songs and you can create playlists as well.
Creating multitrack playlist for LP-16 first you need to create multitrack song(s). You need to select LP-16 as target device in the uTool settings tab, then go to the export tab, and click on the create new song button. In the left window you can select the folder where your mono wav files located, then drag and drop each file from the left window to the right window (LP-16 output channels), save the song.
When you done with the multitrack songs, open the playlist tab seletct the create new playlist then drag and drop your multitrack songs from the left to the right for creating the playlist.
On the export tab you can transfer your songs and playlist from your PC to your USB drive.