Facing Error with Webi Query panel

Hi,

I am working on SAP BO 4.0 and using IDT and also UDT for creating universe, and for the reporting purpose using webi in BI launch pad ...i am facing issue with the webi query panel ,

Actually the problem is while adding objects or filters into the query panel of webi upto some 15 objects it is working fine , if i add more than 1 object getting error like 'An Error Occurred' and same thing continuing for remaining objects (but check integrity is fine in universe),

If we take new query panel for remaining objects here also upto some 15 objects working fine , if i add more than 1 object getting same error..

Can any one suggest me how to resolve it ? Is there any limitations in query panel?

--Ankitha