I also have a lot off .dll errors however the install becomes a lot more stable and actually (halfway runs) some features are still having problems if you install windows media player 10, also you will need to have adobe flash preferable a later version installed under wine also. I have been able to get it to export songs into mp3 so far other formats havent been tried as yet by me as i have spent 8 hours trying to get it to work as my windows crashed and had to install straight Ubuntu Linux. Also i dont know if you have noticed but the (wine emulated) version will not recognize larger memory storage devices, I am also working on this and will post if i get an answer. The .dll issue is aggrivating at best and can actually cause critical crashes at other times so as another user you can rest assured i will be trying to get my magix working as well however i have version 16 and you have 15 i dont know how much difference that will make.

 Oh and just to comment on the below, if we wanted to reverse engineer something like this all we need to do is get the already released lmms software, i am partial to my magix and if i can get it working in linux properly i will be pushing it out to some of my friends, I havent even seen a linux based distro for this program, by the by lmms has a lot of features very similar to magix but it is open source so the user can edit and distrubute it, magix is not and is proprietary, another thing that you might try is checking to make sure you didnt miss any update for your magix as that will resolve some issues.

 Most of the .dll errors are from processing effects channels and may b able to b handled by other tools or VST's that can b freely downloaded and installed.