No solution so far, to get the oem_cust you need to get the ColorOS payload, the OOS one won't have it.
@g4seb
I was able to get the charging animation from ColorOS 12, by running the msm tool to OxygenOS and updating it with the OOS 12 right afterwards(do not flash the oem_cust1, it was probably kept on a secondary partition). But the UI issue remains the same, the real issue is that the new ColorOS 12 notification/quick action bar is totally different from the OOS version, I dunno how to port that over, as this is out of my knowledge level.