couple of things to check,
- Did the transport files get loaded correctly and are they the correct version for your BASIS version
- Can you run transaction /n/QTQVC/SQL and run a simple SQL statement?
- If yes can you extract any tables from SAP e.g a smaller one (T001)
If yes to all of the above you may be running out of allocated memory on the SAP side as the DD03L table is large and also runs a nested query on DD02L for filtering)
I faced the exact same issue, here's what I did to overcome it:
You need to install 2 transports on your SAP ECC system.
Once you have downloaded these from the QV downloads website they need to be pasted into the appropriate folders on your SAP server.
D:/usr/sap/trans/data - E6DR900923
D:/ust/sap/trans/cofiles - E6DK900923
Then go to your SAP system and to transaction STMS - choose the appropriate system you wish to import the transport (dev, qas, prod...)
Then go to Extras -> Other Requests -> Add (type in your transports)