Does it do this every time?
I would re-install madCAM and see if that helps. Also, check the download size of the madCAM43_111123.exe file. It should be 10,493Kb. I mention that because I had an issue a while back (although not the same) and the problem was that my download was incomplete. I downloaded again and it was fine.
Joakim is at Euromold so he may be out of touch for a bit. Hopefully we can figure this out.