We have had some customers that had an issue with RPM-4U dimmed loads. If they dimmed to any level under 100%, the loads would shut off.
We discovered that they had defined the RPMs in the project to be RPM-4As. When we changed these 4As in the software to RPM-4Us, the issue was resolved.
If the RPMs are behaving in a weird manner, a good step to double check is that the RPMs in the software are the same model as the RPMs in the panel.