Hi Marta!
First of all welcome to the Thor Community!
The most updated files are the ones located in the Thor Github’s repository. I would recommend you to use that files instead of Hackaday ones.
About the slacks you found on the Art5&6 pieces… Could you post a video to see what is happening? The vertical one sounds like the bolt that pass through the Art56GearPlate is not tightened enough, but without seeing it is hard to realise.
Hope it helps!
Angel LM