http://bugs.winehq.org/show_bug.cgi?id=30136
--- Comment #7 from Sagawa sagawa.aki+winebugs@gmail.com 2012-12-28 03:03:31 CST --- I confirmed Pokemon Essentials's issue.
I think it is related to be Bug 10791 or Bug 9027. I removed all Audio\BGM*.mid files, then it works on wine without background music.
'winetricks dmusic' might help the issue but I've not tried.