Mutable: Population - No preview in the Population Class editor

In UE 5.5. When attempting to Test Population Class in the Population class editor, nothing is generated in the preview window. The source for my class is CO_Character asset inside Mutable Sample project.
Am I missing something what has changed since 5.4 version?
ZT

I also encountered this problem, did you find a solution? Thanks!

Unfortunately not … Experimental state of the plugin

Did you get any of the population features to work? The editor doesn’t show any preview and trying to call generate pops in blueprint from a population class also doesn’t yield any results.