Manipulating test cases and execution in API

I have folders named Functional and Regression under test repository and each of those has folders named as requirements with test cases in then. Functional and Regression folders are of type Phase. And sub folders are of type module. I want to create cycles under execution based on the folders Functional and Regression but looks like I cannot use folder type module using Create Cycle phase from the Test Repository. I also understand that I cannot create cycle based on TC tree type Phase. Or am I missing some option? Can I create Cycles based on TC tree folder of Phase type? After that is done, how can I assign unassigned cases to their designer via API? 

Another issue I have is appears that when I try to move test case folders to parent folder testcasetree/move/foldertomoveid/to/0 or same with release ID after slash at the end does not work. Is there other way to moce test case folder to release parent folder?