"Ok... after a debugging session with Fred, InitEngine3D now works again."
Fred's debugging session with me consisted of an e-mail with a link to download a de-bug version of Purebasic, and then Fred wanting to know what the OGRE.log file said. That was it. Nothing was corrected in our debugging session because everything reported was fine.
How did your debug session go and what was discovered? Perhaps the same problem you have is the same problem myself and others have.