I know that the beta team is really having issues with grub2 and uefi but on my test case I say partial sucess.
With legacy mode the beta boots fine on my one and only UEFI hardware (a HP Pavillion 15-n211dx laptop) using grub 2.
boots an runs fine on legacy mode, does squat on UEFI mode but UEFI is evil anyway thus why i dont use it.
Just hope to put out my test case, software end looks fine but i will be rolling this machine back to Mageia 4 here soon as I dont want its owner to be running a beta.
Not sure how much more useful this can be to the developers but its something at least.