Ok... seem to get random crashes. 1 time I got the chance to make a dump, 3 times the c++ runtime told me he was stopped in an unknown way, 3 times I crashed without any message or possibility of making a dmp-file. Not sure if this issue has to do something with movement, but surely with the graphics. When I turned off the vertex buffer object, it seemed to work for about half a minute, than crashed without a warning. Gave it a second try than and crashed immediately.