This is pretty appalling alright. Its the lack of feedback that is most annoying. I can tell that launch daemon is trying to unzip the downloaded package, which I can see in the Finder, but it takes so long that it is impossible to know it is is stuck or not. The logs are not any good. All I can see is that the last log was that installD was extracting the file, and is running at between 150-300% of CPU. When I sample it is in somewhere in deflate or some copy method. I suspect I can just wait around, that is more than the 30 minutes and counting since it actually downloaded. I see a lot of this:
1995 BOMCopierCopyWithOptions (in Bom) + 1952 [0x1aa886154]
+ 1995 _copyFromCPIO (in Bom) + 968 [0x1aa8a795c]
+ 1995 _copyDir (in Bom) + 1708 [0x1aa88a6e0]
+ 1995 _copyFromCPIO (in Bom) + 968 [0x1aa8a795c]
Most of the solutions here are to download again, but I have a slow enough connection.
Update:
I tried to kill launchD in the hope of running the PKG which I could find from running open /var/log/install.log and see what was being extracted, but get this. If you kill the app, ie launchD, that is not clearly working it will deliberately delete that PKG. They have literally put in code on a SIGTerm to delete something that will maybe help you fix the issue. Maybe to be fair that is to recover disk space, however it means I have to download again. Grrr.