Loose wall cupboards

Hello everyone, I'm new to all this so please be gentle with me (it's taken me half an hour to find out how to post a question!).  I bought a Bailey Deville early last year and was over the moon with it.  However on it's last of many outings, I realised that the wall units over the sink area had dropped.  On further investigation it became apparent that many (no most) of the screws holding it to the wall had come adrift.  It was now hanging from the ceiling, which had also by now dropped.  Am I alright in propping the whole cabinet up with a wooden frame or do I really need to strip everything back, remove and repair the wall and then put it all back (probably beyond my capabilities and finances)?  This is an old caravan but a much loved one and everything else works.  I did not have anything heavy in the cupboards but do have to drive on rough farm tracks (slowly) so it does get shaken about a bit.

Thanks in advance

auntyjan