After initial install, the computer cannot complete reboot without the patch “MacOS Post install” (see step 13 above). This will require a hard shut down (hold down the power button if it is stuck) and restart holding down the alt/option key until you can select the installer again. This time, do not reinstall the OS but click on the button on the side (or double click it), or select in the pull down menu.
This will need to be repeated for updates, if new updates also get stuck.
Hope this helps.
A couple of things that I noticed: After the install (before the patcher, the screen on my MBA mid-2011 went white (since it could not reboot without the patcher). I did a hard shutdown and restarted holding the option key to get back to the installer for the post install patch.
Second, updates from both the patcher (for mitigating known update issues) required a restart which worked but the second time through with Mojave updates got stuck similar to the original install and required a re-post-install patching like before. This could be disturbing for folks who don’t realize this.