The attached file is a model of this part from Newport: M-PS-KF.  I would like to use it in my model, but I would like to at the very least have it present in the "open" form, and if not be completely flexible (i.e. two separate parts in an assembly with one being flexible).  Is this possible?

I did find the Split command (i.e. Insert > Molds > Split), but it seemed very rudimentary (e.g. not even being able to split along a curved surface).