I'm don't know why a few are having issues (locked on pink screen at boot) but I'd seriously just try a new config and new install of 4.1. It doesn't take that long to setup and see if there was something in your OS 4.1 changes that was causing the issue or not.
Start a basic config, just enough to get the system up and running. You can always "add" more hardware to the config just like doing so to a real Amiga
