In order to try and isolate the problem can we remove SQL Developer from the loop...
Can you try executing the CREATE CACHE GROUP statement directly from ttIsql. You will need to connect to the DSN providing all the necessary credentials. For example if your DSN is 'MYHLR' then it would look somehting like:
Where 'ttpwd' is the TimesTen password for the 'HLR' user and 'orapwd' is the Oracle password for the HLR user.
Once connected just paste in the CREATE CACHE GROUP command and see if it works. If you get an error proceed to troubleshoot it. If it works okay in ttIsql then the problem is specific to SQL Developer. If it doesn't work in ttIsql then you have soem other issues that need to be resolved first.
Okay, this is a bug. I just tried it myself and I see the same issue. The problem is due to the mixed case table name. I will log a bug on this but for now the only workaround is to not use mixed case table names.
We can't say yet when this will be fixed as it has only just been logged. I would suspect that it will be at least a few months before a release that includes a fix but it is only a guess at this stage.