"I would guess the shelf is down already otherwise the roof wouldnt have dropped originally. The resistance on the shelf knobs is because you are trying to lift against the roof thats sat on it.
To start with, You need to unlatch the roof from the rear bulkhead, pull the red hoop and manually get the roof atleast to the half way point and then see if the buttons will operate in either direction"
Do you mean the roof un latches by pulling the red hoop? If not how do I unlatch the roof?
Can I not turn the handles because the roof is down?
Do they only turn when the roof is up?