SETI does funny stuff to clients (WCG too for that matter), but it will most likely be that WCG has had it's time used from the Resource shares.

That what you saw downloading is the fixed science app files, images and such. You can force the hand to suspend SETI for a few minutes in the BOINC Manager Project tab and allow work fetch for WCG, by hitting the update tab.

Plz be sure to first set "Leave Application in Memory when Preempted" in the Local prefs if not on, else your running tasks will unload.