FM Conditional Build Tags Not Processed Correctly in RH

I am using TCS 4, fully updated.

I have Frame books that are linked to Robohelp projects; in the RH project FM Conversion settings, I have Apply FrameMaker Conditional Text Built Expressions selected.

In FrameMaker, I have the conditional text set the way I need it, and the content displays correctly.  Two CB tags are used in the content; we'll just call them A and B.  In Frame, CBT A is displayed.  When I update the project in RH, I get CBT B instead.

I then set Frame to display CBT B.  This time, RH correctly displayed CBT B.

Just to try an eliminate random weirdness, I set the entire tst file to unconditional.  It ALL displayed in RH.  But then I re-applied the two CBTs.  Back to square one.

Getting very frustrated w. TCS4.  Never had this problem in earlier versions.

Does anyone have any suggestions?  An option of last resort would be to unselect the Apply FrameMaker Conditional Text Built Expressions option and process CBTs in RH; it appears to work, but would make managing the projects--particularly context IDs--maddening. I prefer to see the content before it's generated.

Does anyone have any ideas?