FYI, I found a workaround, but I'm not exactly sure WHY it fixed the problem.

After issuing the TableUpdate() command on the CA's cursor, I do a SEEK on the base table for the current primary key value. Once that seek is complete, the cursor keeps the changed value on the grid.

In any case, a workaround is a workaround, no matter whether you understand it or not. Thanks for your help!

Ben