Abbreviations disappearing in TM language resource settings

Hi all,

I am in a project where I want to use a custom abbreviation list.

For instance, there is a lot of use of Russian м. (for meters) and C. (for Centigrade), so I don't want them to be abbreviations.

On the other hand, there are custom abbreviations like Russian (Р. р.) and (выс.) that I want to keep.

I placed these in the TM that is first (or only) in the list of TMs so they will be used for segmentation.

However, they only seem to work when I create a new TM.

If I add abbreviations to the existing TM, they seem to be there, but when I restart Trados, the abbreviations I added are gone from the list.
The only way for abbreviations to stick in a TM seems to be to create a new TM with all desired changes to the abbreviation list.

Very frustrating!

Any advice would be most welcome.

Thanks.

Tom Fennell