I had a problem at portable version and i do not actually know if it is already fixed...
When changing between PCs and drive letter changes, the program:
Crashes or can´t open last file or lost playlists
I noticed that in settings file and "Xion.m3u" all paths are not relative which causes the problem!
I fixed it once by changing all paths to relative, but simply when program re-writes this file all config is lost again.
...so, please tell me if it is fixed or not on betas.