I've done that as well and I've also checked the Adagio Manual and the cell I have selected does contain a function listed in order to drill down.
Here is an example formula =-SUM(ADGET("gldata.BAL",$A10))
According to the Adagio manual Pag 3-93 If you have the function of ADGET you should be able to drill down.
Does it have something to do with the version of Adagio we have?