iTunes 12.6 very slow to start/run and not accessing store after update on Windows 7

I'm on Windows 7 SP1 with all the available updates for my OS installed, and installed the 12.6 update for iTunes the other night.

The next morning I noticed that when I started iTunes, that while it looked to have loaded up my cursor was just spinning over it. About 10 minutes later it was allowing me to go in and edit my playlists so I thought that was just something weird and moved on.

Later though, I saw that my podcasts weren't updating and that when I attempt to go to the store to manually download them I was getting the same behavior as on startup (seems to lock-up, cursor spinning) though it never loads into the store and the main area just stays white.

I should note that I can download podcasts "manually" on my iPod, sync that with iTunes to transfer the podcasts to my computer, edit my playlists and then sync my iPod again to get this going. Though even then during the sync things aren't showing up properly (I see files appear on my iPod well before the "copying files" stage of the sync starts on iTunes).

Things I've tried to fix this:

1. Run the iTunes installer again in case something was broken during the install. No change.

2. Do a System Restore to several days back as I couldn't find a 12.5.x installer for iTunes to rollback with. No change.

3. Restart system multiple times during multiple little tests that had no change to the behavior.

As I've seen a few other threads that seem similar to mine here, though in those it seems like iTunes won't start at all so mine is getting a little further, with people after the 12.6 update I thought I'd see if anyone has any suggestions or knows of a fix/workaround to the behavior to get iTunes up and running again.