Using multiple TMs as a lookup

Hi,

A customer wants to switch from British English (BE) to American English (AE), and I'd like to continue using the BE TM in projects as a lookup, as there's so much content in there that's still useful. For some reason, however, this isn't working. I'm aware that Studio treats American and British English as distinct languages, yet I'm sure that this has worked in the past for other customers.

I create the project using a customer project template containing the new AE TM. I add the files and click 'Finish', then go into the Project Settings and add the existing BE TM. Studio then asks me to select the supported language pairs (in this case DE->BE) that differ from those in the project (DE->AE). Once the BE TM has been added, I uncheck the 'Update' box, as I no longer want to update this TM with AE entries, but I leave the remaining boxes (Enabled, Lookup, Concordance) checked. These boxes are likewise checked (along with Update) for the AE TM, and there is a subordinated project TM that is also enabled. Studio then asks me if I would like to prepare the project files for the new target languages. I click 'No' and can start working. Unfortunately, however, nothing from the BE TM shows up, either in the Translation Results window or in Concordance.

Have I overlooked something here or am I just remembering incorrectly that it ever worked in the first place!?

Many thanks,

Andy