This is a very brief question with a very long intro, which I've provided for context.
I have recently been trying to install the AMD 64 bit version of Ubuntu 14.04.1 onto my Acer V11 Touch. This laptop originally ships with Windows 8.1, but I happily deleted that straight away.
The boot was done in EFI, with secure boot on, and through the standard install option from a USB created with pendrivelinux. It all seemed to go well and install correctly, but then I came across a problem which appears to be very common with Ubuntu installs: I had no boot option; my computer booted straight into the USB I used for the install, and the F12 boot menu showed no other possible selection. Upon inspection, I had what appeared to be the correct partitions (a FAT32 efi partition, and ext4 partition with Ubuntu on it, and a Linux swap partition).
I tried all the standard fixes involving things like boot-repair to recover GRUB, but with no luck. I successfully installed a 32-bit version in Legacy BIOS, but this felt like a cop-out. What I've just done, and appears to have worked, is to go into the F2 BIOS menu, and under the "security" tab, enter an option called "Select an UEFI file as trusted for executing", where I followed the options "HDD0", "EFI", "ubuntu", and finally "shimx64.efi". I now have a boot option which appears to load Ubuntu!
My question is, what exactly did I do by selecting shimx64.efi as trusted for executing, is it actually the correct thing to do to fix my problem, and can I expect any repercussions some way down the line for dodgy practice..? If it IS the solution I was looking for (as it appears to be), why doesn't it happen automatically?