Yes, section c is very frustrating. I’m currently trying to pass it (3rd try!) I think that the vignettes I ordered from PPI were helpful, but I wouldn’t bother with the diagnostic vignettes that clarb offers. They are expensive and the graders do not provide very much information.
Clarb’s parking lot requirements do not make a lot of sense, but I’ve tried to put that out of my mind and try to understand how to pass the test rather than learning the material.