Updated question - it looks like this might be related to an ampersand in the list of values used by the InList function ( e.g. InList(ColumnName, "Blah,BlahBlah,Blah & Blah,Not Blah" )
Spaces seem to be OK, but not the ampersand...
I've got a pretty nifty prompted ( mandatory ) presentation variable which works quite nicely ... the first time it's set.
When I click and change choices it does not update the insight, but if I change choices, edit the insight ( making no changes ) and then save it honors the newly selected value. As you might imagine that is not quite as impressive as it could be.
I don't know if it's a browser caching issue ( tried both Chrome and Firefox ) or something else, but the same logic works with Online Store data in a different environment ( also a newer release - 2022.9.0 v 2022.11.1 so that may be a factor ).
Interesting - it seems it *may* have been a special character issue, but <shrug> I dunno. I deleted and re-typed the spaces -- literally placed the cursor in front of the space, hit DELETE and then SPACEBAR -- and it worked. Something funky in there somewhere.