Hi Boris, thanks again for your prompt reply. I tried your suggestions and they work. The only thing which still bothers me is that all the STL files which I opened (propblade and prophub), are STL graphic files. Despite being able to open the files, I am still limited to only viewing the models and not able to edit the geometry of the model ie. editing the radius of a curve or changing the propblade profile.
Once I unpacked the .msim file, the stl files appear as META-stl files. I renamed them into stl files and by doing so I can open them in a CAD sofware (Solidworks 2014). The shown model is a STL Graphics as shown in the attached picture. How can I get around this problem, in order to be able to do some geometric changes onto the models?
I think this is more of an additional question, more related to the CAD software rather than MapleSim. It is fine if it is beyond your scope. You have already been a great help so far by answering my previous questions!