I am also having difficulties with the new import system in 5.5.
I have models that I purchased online for 3ds max, and converted to be used in UE, usually when I do this, I only plug materials into the existing slots in max, and when I import them to UE no matter how many ID slots the model has, UE recognizes the materials I have and only makes slots for those materials.
In my specific case I have fitness equipment that has 108 slots in max, but the 108 slots only actually use 5 materials (don’t @ me, I didn’t model it). Now, when I import this into 5.3 it comes in with just 5 slots for materials, as expected. In 5.5 however it creates a slot for every ID that the multi material in max has (108). I’ve been losing my mind today, thinking I did something different in my workflow, but then I checked 5.3 and everything worked as it always does. Please help, I can’t disable the interchange framework because I need it for other assets in the scene that I use datasmith for. What do I need to do that Unreal stops creating all those material slots??
My hotfix workaround is to import them in 5.3 and then migrate them, but that can’t be a long term solution.