pymat seemed to be compiled against an older Matlab Version. Just pointed that paths in the setup.py to my Matlab Installation, installed VS 2008 and created a new pymat installer. Everything works fine now.
Look for the following variables in setup.py and point them to your matlab installation
matlab_dir ='C:\Program Files (x86)\MATLAB\R2013b'
matlab_plat = 'win32\microsoft'
Create installer with:
python setup.py bdist_wininst