system installation - Ubuntu 16.10 Dual Boot error - 'grub-efi-amd64-signed' package failed to install

I'm currently trying to dual boot Ubuntu 16.10 alongside Windows 10 on a Dell XPS 13 (series 7).

I've basically followed this guide! which involves:

1.) Changing from IDE to AHCI mode

2.) Enabling 'UEFI Network Stack' via the BIOS
3.) Booting via USB - (with Ubuntu Boot disk created via Rufus or Etcher)
4.) Installing Ubuntu via USB

Install hums along as per usual until it comes to installing Grub where it shows an error:

"The 'grub-efi-amd64-signed' package failed to install into /target/.
Without the GRUB boot load, the installed system will not boot."

This is a new laptop so I haven't installed Ubuntu on the machine yet, but I have installed it on old laptops and am reasonably familiar with the setup process so I've tried a number of alternative solutions including:
- ensuring updates are downloaded during the install
- specifying the install partitions for the root, swap and boot
- Installing via DVD instead of USB
- Making a sandwich

Anyway, I haven't had any luck and would be grateful for suggestions/ideas as after a lot of googling I'm out of them.

EDIT:

Okay, so I've managed to get it working after a lot of trial and error.

Unfortunately I'm not sure if it provides useful information for others who might experience the same issue.

Here are the steps I took:

1. Suspecting it may be an issue with Ubuntu 16.10, I undertook the painful process of downloading 16.04 (LTS). - painful due to my slow internet -


2. I updated my BIOS and Hard drive (Toshiba NVMe) firmware from the Dell website (Dell XPS 13 9360).



3. Delete the old ubuntu EFI entries via Windows (in case it was causing the error).


4. Installing Ubuntu 16.04 via USB (UEFI mode) - made it past previous GRUB error above, but received error "'grub-install /dev/nvme failed. This is a fatal error.'". Installation halted.


5. Launched live-usb and repaired grub via 'Boot Repair' with 'secure-boot' unchecked in the 'advanced' option.

This worked.

No idea if my computer is likely to explode, but everything seems fine.

Btw, this has been reported by a number of other users eg example 1 and example 2

EDIT 2:

One other thing I had to do (possibly as the install halted early) was check and replace/repair missing files via instructions below:
Find (and reinstall) packages with corrupted files (without breaking anything)