Matlab builder NE/ MCR on windows 8 problem

I have compiled some matlab functions using Matlab R2012a into .net DLL files. and everything is working as it should. i am using WPF/C# .net 4.5 on windows 7 64bit and my program works ok.

however we are now transferring and testing our program on windows 8 pro. we have a problem in runtime - we are using of course MCR R2012a in order to run the .dll files. we can't load the classes or functions in win8 and our program crashes. have anyone came across this problem? will it help if we will compile the functions using Matlab R2013a?