Hi Ben,

Lists don't have built-in support for UUID right now. We had to add it for datasets so that you could refer to rows solely by the UUID, instead of by the other types of keys that datasets already supported.

For now with lists, you can specify the key as a VARCHAR and use the LABKEY.Utils.generateUUID() to set its value when you insert a new row.

In the future, it would be great for lists to natively support EntityId/UUID keys so that you don't have to make up a key value for new rows yourself.

Thanks,
Josh