There is no registry hack that is going to make this happen for you.
The codecpack you are using is over 6 yrs old. Uninstall that archaic codecpack and Icaros (Icaros is developed on my forum) before installing the Shark007 codecs (which include Icaros).
It is quite simple to acheive the results you seek. You just have to read a bit.
When you 1st install the Shark007 codecs, you are taken to a Setup and usage
This page has all of your answers for anything playback related.
For your specific issue, look for the section beginning with "If an MP4 file fails to play properly"