GL Drill down is great(ish:o) in Expert; assuming the GL Map is set to post in detail - or even not...
Either way, Expert relies on the table GLA_JRNL_TRAN (if you're not familiar with that table then check it out) ... However, if you try and use it via SQL or any reporting tool to get to the sub-ledger tables then (and as we say in the UK) "... It runs like a dog".
Because GL_TRAN_UNO is quite important between GLT_JRNL and the sub ledgers.
So put an index, non unique, on GLA_JRNL_TRAN.GL_ROW_UNO - Remembering to do so via DBEditor
Because the chances are that Aderant missed that rather important item :D
In my experience it makes a huge difference, and Aderant support will have no problems with you doing so.