Hey ,
Thank you so much for looking into this!
Well actually it works without AdvancedSessions Plugin but compiling my code which worked without problems in 4.8 and earlier gives me also #define errors.
Your tip about VS 2015 is something i will try out!
I could give you the SVN Data of our team server so you can sync the project to look into that if you need to, just tell me!
Thank you very much!