Ran into a similar problem. I have ONE copy of PanX and one of Pan 6 on my iMac. Pan X has an icon in the dock, Pan 6 doesn’t. When I opened PanX today I got a notice that an upgrade from 24 to 25 was available, which I clicked on. Seemed to download OK, then I got a notice that the download was corrupted, couldn’t be unpacked. But your screen offered only the option to install, no obvious way to reload. Quitting the program didn’t help; it stayed at "install"only. Shortening the story, I finally hit install anyway, everything seemed to work, the Panorama installer claimed it was successful, the upper left now said it was --25(3901), but the listing in the App folder on my hard disk still said 24, with its older build number, as did the icon in the dock. Saving the program didn’t change the 24 to 25 in the App folder, so I manually changed it, tossed the icon and made a new one, figuring these’s always the revert button. Somewhat surprisingly, everything seems to be working normally now; when I check for updates your same installer appears and says b25 is already installed. Whew!