Thank you Gravemind2015, and lost101 for your replies, I agree that the screen is most likely at fault here.@qwertyiapine - The replacement screen is the cause of the bootloop. It would boot correctly if Android 5.1.1 was still on the phone. As already suggested, the only way (now) out of this situation is to get an original Motorola screen.
Related: http://forum.xda-developers.com/2015-moto-g/help/screen-digitizer-giving-bootloop-t3369386
Is there anything specific to look for on a generic screen that differs from a genuine oem part to differentiate between the two?
I decided to go ahead and remove the screen, and plug the phone into the charger as I do not think it has much charge, my theory being that the screen will not light up when the phone wakes so the battery may get a chance to charge up.
I also wondered if the phone would start up without the screen.
After some rumbles from the buzzer at the same intervals as the phone did when the screen went on and off the phone went quiet, I pressed the power button, nothing happened, then I pressed it again and I heard the distinct 'click' sound phones make when you lock the screen.
I connected the screen ribbon but the phone buzzed and reset, but the logo began to animate and the phone booted up and presented me with the language selection page on initial setup.
I could not keep the screen steady and the ribbon in the connector to lock the cable in place and it went off.
I was back with the boot loop, and several attempts to successfully repeat what I did has resulted in a screen that will no longer come on.
I don't know if the screen has had it, or the phone.
I saw the tiny ribbon that connects onto the flexi at the top of the screen had come out so I put it back, but nothing from the screen.
The phone will buzz when connected ton a charger.
I either caught the phone just at the right time, or the screen does work with the phone and something else is causing the loop.
I was dubious about buying a scrfeen in case the phone was account locked. At least I know it is not.
The issue now is that the only oem screen I can find for sale is from a seller in the US on ebay. total including shipping is £52.90p and I do not even know if it will work.
It is a lot to gamble, and the phones can be had new with warranty for £129.
As was already suggested is the phone needs a screen to get the bootloader unlocked, then it can be downgraded with a cheaper screen fitted. I think mine has fried.
I don't mind buying the oem screen, it is the £24 shipping I don't like!
I am surprised that there is a real lack of genuine parts when doing a search online.
Do any of you know a UK retailer?
Thanks for your help.