Uploaded an update fixing these issues. I reordered the folder structure and fixed conflicts. Issue was mainly because some of the shaders referenced some utility shaders, but those had changed between packs. There was some other tweaks and I also tried to port newer features from newer packs to the earlier ones, but not all of the new features are yet ported because my priority was to make the packs compatible first!
I want to thank you for your help. I wouldn't have noticed all the conflicts myself