Using the firmware provided in RaspioF3-production-v22-241114_RC.dfu (from Roboteq tech support) I am able to load and run Microbasic scripts.
There is one caveat: Do not move from the "Setup" tab to the "Scripting" tab in the PC Utility with the RIO powered. This will cause the RIO to "lock." Instead, remove power from the RIO and then go to the "Scripting" tab. Reapply power to the RIO and you can now download the script. The script can then be run with the "Run" button on the utility or via one of the direct communication channels (e.g., riocom on the Raspberry) with the !R command.