High Sierra bricked my iMac .. com.apple.DiskManagement error 0

You don't have to erase your disk. Your data is safe, even when the com.apple.DiskManagement error 0 appears. You need macOS Sierra, the former not the latter High Sierra, have it in an USB, restart your computer erasing PRAM, then restart it again with command-R, choose reinstall OS from USB, then you'll end up with the old macOS Sierra and your data intact. I did that since I tried to install High Serra unsuccessfully on launch day, when my computer got the infamous install error. Now, I'm still waiting for High Sierra to be more mature to give it a try again, whereas I'm writing this post in my usable MacBook Pro pretty fine.

On my first set of attempts, I too got into that endless boot process. For me it was because the system was so messed up that it would not see the Wireless Keyboard CMD+R keys before the Apple Logo popped up and installer restarted.

My solution was to get out my old USB keyboard from an ancient iMac and use it for the restart with CMD+R. It did not miss holding down the keys on the USB keyboard and went right into the recovery screen. It was a relief but not really a surprise. I thought about using a USB mouse too but all you really need is a good read of the CMD+R keys before the Apple logo pops up and then it's off to Recovery. There it actually reads the wireless mouse and keyboard just fine.

Regarding Apple Support:

One thing that seems to help with Apple Support is that I always seem to have one or more gadgets on an Apple Support contract ... and because I'm on the Automatic upgrade program, Apple Support is always current for my iPhone. I think showing up as an Apple support customer when you call, might help with priority, even if that particular product is not under contract.

Having said all of that, a 'Saturday' appointment makes it sound like they're swamped by installation problems, so I'm not sure even an Apple Support customer will get instant service.

But give the USB keyboard a try ... any USB keyboard will do, so just borrow one from a PC if needed. On a PC keyboard, I think the Windows Key = Command but I don't have one to try.

The good news is the systems isn't really bricked. The BIOS is working so the problem is that it's redirecting to the installation loop because there's no external command to stop it. If it were bricked, the screen would be Black, white or just a mess of garbage.

My first attempt failed (Mac Mini Late 2012, HDD) but I retried with the updated installer from the App Store (dated 5th October) and that worked fine.

So, it's either just luck, or the failed install/restore from TM corrected something wrong on my HD, or Apple fixed something in the installer.

I think the 10.13.1 will be out soon and maybe will get some clarity from Apple on what the problem was and what they have changed.

Indeed you do have the latest (updated) version and I have seen posts that have installed this successfully. I was getting around to trying it on my 15"MBP but I think that I will wait until 13.1 emerges (in developer Beta as we speak) and then see if the forums erupt with more problems. What with High Sierra and IOS 11 (now in 3rd release) I am rapidly loosing faith in Apple. I have already sold all of my Apple shares.

I was stuck in the terrifying loop of "Startup Chime -> Weird error message and loading bar for 2 seconds -> Repeat"

I used cmd-R and was taken to the Utilities screen where I was able to restore from backup. Luckily, I had made a backup about an hour before installing.

Apple, I as well am rather tech savvy. I have 12 terabytes of sensitive information cleared out. I purchased a brand new HDD as well. Bricked immediately. I would like to know what kind of compensation package you're putting together for this?

HS bricked my 2011 MacBook Pro also! ***!

Does Putnik's answer (above) work for finding old installers?

May I know how's your installation method? have you tried reinstall it using a disk installer such as ext HDD or flash disk?

same here very angry. what is this Microsoft???

I have the same problem, hope Apple will come with a fix ASAP!

Same happening to my 27" iMac. Have tried similar approaches to what others have stated. Still nothing.

Is there a way to download Sierra? It's not in the App Store anymore.

I you login to your account, in "Categories", under "Hidden Items", there is "redownloadable Purchases". My previous OS's are listed there.