Hi Kevin,
the problem is, the same difficulties apear at normal windows 8.1 as well. It has nothing to do with limitations of my OS (which are 100% equal to the ones for normal windows 8.1) or my OEM partner. It is simply given by the fact, that your custommodeapp doesnt work under windows 8.1, as already stated by several people above.
I am still waiting for someone who can express, if this concern is going to be addressed in the near future, or if I should switch to another manufacturer which is able to provide basic settings for their "high tech" products.