To be more precise, if the Network Activity window is open when I launch OW5.5sp4, I see network activity reported. One item labeled Web Pages remains. The triangle in front of it will swivel but won't stay closed (pointing right). The last document loaded also has a swiveling ineffective triangle. There was an HTML resource on that page that had a blue dot at the end, but when I clicked on it, it disappeared. Clicking on the document or the resource shows its address below the field. The text below the field cannot be selected, but the Status is FIXME. The progress for the resource says 333 bytes of 333 bytes, at 0 bytes per second about 10 minutes elapsed (since I launched OW). The progress for the document is 21.2 kB of 21.2 kB at 32 bytes per second.
I don't think it matters which page was loaded in my default workspace, but it's the login page at geocaching.com:
http://www.geocaching.com/login/
And nothing I've done since the first launch has caused any change in the Network Activity window. I see only those two items.
I'm going to see what happens when I switch workspaces. Nothing happened in the Network Activity window as that other workspace loaded a bunch of things including downloading two PDF files that I had looked at weeks ago and had tabs looking at?
So, no, this isn't working as expected for me. I'm not sure how it can be this broken for me but fairly normal for you.