As I’ve been building in studio I thought to try the “Cast Shadow” tick box property on parts/meshes/unions so as to have them not cast a shadow. I realized that once I saved the game and came back to development, the property reverts back to the default state (which is on/true).
I tested this in multiple places and with all parts/meshes/unions. It reverts your choice every time you save your game. I’m not sure when this started happening as I’ve just started using this feature. I think this is a great feature, but unfortunately it’s rendered useless until this bug is fixed.
Same bug is happening for me as well, I don’t know if you are getting what he was saying, he is not mentioning that he can only use “ShadowMap” on Roblox Studio, but rather when you toggle the “CastShadow” property to false, save, then rejoin studio, the “CastShadow” property reverts back to true instead of false.
I don’t know if that’s intentional or not, it’s really annoying.