I think I found bug in reference GUI. On Windows when username is in cyrillic the wallet won't start saying it's already runnning. It's stuck on checking for .lock file. Also you won't be able to save wallet to folder with cyrillic name. Moreover if you save wallet to folder named in latin but with filename it in cyrillic you will got mess like РџРµСЂРµРІС–СЂРєР°.wallet
And last one - when CLI daemon is running and GUI wallet is launching with Proxying INode it will open, but it won't save wallet so people can loose coins because on restart they will have new wallet with different adress wchich will not be saved to disk.
I tried DigitalNote and Bytecoin.
The problem is with QT Qdir and QFile I guess.