The Transfer tab shows details in real time when something is actually downloading or uploading. At other times it is empty.

All downloads and upload action is logged in the Messages tab.

The upload process in BOINC is twofold.
1. it uploads the data you crunched to a place on the server.
2. it reports the task to the science database.

As it looks, you may have uploaded, but not reported yet. Reporting of tasks happens:
1) 24 hours after completion (was Connect every X after completion).
2) 24 hours before report is due.
3) Connect every X before report is due.
4) On a trickle up message (CPDN only so far).
5) On a request for more work.
6) On a manual update. (Projects tab, select Seti, click Update)