After upgrade the new version , the issue for using RDP sessions. as follows:
MacOS: 14.6.1 (23G93)
RDM version : Version 2025.1.12.4 (March 12, 2025)

Hello and thank you for reaching us.
Before anything, what are your display settings? are they all on default?
You can see that in the properties of the entry > RDP > Display.
Best regards,
Michel Lambert