Hi! Sorry if this is a late reply but I was just passing by and I saw your comment haha
Maybe if you select all notes and then click reset, then with all notes selected, right click on one of them an then click property, then click on clear and doble click on STP, flags and BRE. Then with all notes selected click P2P3, you have to do all of this everytime you use an utau in an ust you downloaded. Idk if this will solve your problem though, but probably it will