Fed Ex Module Numinix Product Fields dimensional shipping - set up problem ZC1.3.8a

I am trying to install the Fed Ex module and use dimensional shipping on ZC 1.3.8a. I installed fedex_1-4-5, NuminixProductFields v1.0.0 - i.e. uploaded all the files, ran the sql patch. It looks like everything installed ok. But...

When I try to add data to the new fields (e.g. Select Dimensional Units:, Length, Width, etc. ) created by NuminixProductField, the fields do not update - the data does not appear to be writing to the db.

Anyone else have this problem. Any ideas of what might be wrong?

I am getting FedEx rates displayed on checkout screens so I think that part is working ok.

Thanks!