Installing FM19 took weeks, with lots of exchanges between our local IT support and Adobe: I felt it shouldn't have. Now I'm daringly trying to install the latest upgrade, and two things I remember from the original FM19 install are as bad as they ever were. Thing the first, the download speed is impossibly slow; after about fifteen minutes the progress bar shows around 6% and the promise '16 to 18 minutes to go' … and stays there. I cancelled after a couple of hours. Thing the second, an error message at the start about a conflict between FM and the Character Map application, when then app isn't even open. Solved this one by launching the upgrader, opening the app myself and closing the app again.
Next move, ask local IT support to download the upgrader for me: but why should I need to do this?
Sounds like there are some specific issues unique to your environment - I haven't heard of any issues with downloading FM2019.
I suspect the speed (or lack of it!) it could be something to do with corporate firewall settings, but that doesn't explain the Character map conflict. Local support downloaded the updater (which is not labelled 'updater', but never mind) and sent it to me. This time it ran rather faster, indeed, until somewhere around 90% where it reported it was unable to delete a FrameMaker- specific file somewhere in the install folders … once again, manual intervention solved the problem but left me a little unhappy about the lack of robustness.
Anyway, update now installed: time to check what improvements it has brought.