Similar problem happening to me as well. My initial set up didn't go as smoothly though. It crashed halfway through. The machine rebooted and put me into Unity, though, so I've been proceeding as if all is well.

Later I did the same as you and also for me every thing seems to be ok.  

Gert

Had the same exact thing happen to me. I'm slightly concerned that after I restarted and I ran the soft ware update again it said everything was up-to-date. I'm more inclined to think this is a false positive than the truth, any way to confirm?

I'm having the same problem. The update is hanging on "Configuring grub-efi-amd64." I tried force closing it, but then the system would not reboot and I had to restore the factory image. 

It's hanging on this step again. What should I do?

I also seem to have the same problem. I just received my new Dell XPS 13 with Ubuntu, ran the software updater and it seems to be stuck at  "Configuring grub-efi-amd64. The Software Updater window is grayed out.

What do I do?

After waiting for more than an hour the problem seems to have resolved itself. I noticed that there was a compiler process  "cc1" constantly running while Software Updater was frozen . Maybe this software component needs to compile for an hour an a half to install?

I would recommend doing a clean install of Ubuntu 15.04. I had the same problem you were describing, but now everything works great.

was this issue ever solved?

any additional thoughts anyone?

i'm stuck at at configuring grub-efi-amd64

Okay, I believe I solved this problem just by sudo apt-get update and then sudo apt-get install grub-efi-amd64 before running the software updater.

after running these commands i was prompted to either overwrite my current cfg for grub or keep my old one.  i chose to overwrite and the update worked fine and then I ran the software updater with no trouble.

Just ran into this same problem! After getting stuck on the update I eventually attempted to reboot, at which point the kernal error screen came up and I was forced to power it off.

When I started it back up it wouldn't boot into Ubuntu and instead just stayed on the DELL logo, luckily you can restore it to the factory settings from here:

1) Press F12 on the DELL logo

2) When the BIOS comes up, select "Ubuntu" (under boot devices I believe)

3) From there you should see an option to restore it to factory settings, select that then follow the options and you can begin again.... this time without starting the fatal update :p