The thing is, it's random. Sometimes it works, sometimes not. And yesterday, I got what appeared to be a partial display -- the matrix of thumbnails down the side and about ten or twelve of the blue bars with numbers. I just now got it to show after about eight tries back and forth between two PBase tabs in Firefox. It all supports my theory that something at the PBase end is timing out if data collection is slow, then just going away without posting an error.
I imagine in due time it will magically start working again.