So the original source is a Legacy BIOS system with an MBR disk? If so, then it would be a whole lot easier if you were using Windows 10 1709 (or Server 2016 Version 1709) where the MBR2GPT tool was introduced, but if not, conversion is possible, but involves some hoops to achieve in a VM environment. If that's what you need to do, I would recommend skipping viBoot and just working with Hyper-V directly, doing the following:
- Create a new Gen 2 VM and make sure it will be able to access your Reflect image file, either through VM networking or by creating a new virtual disk, attaching it to your host, copying the image file into it, disconnecting it from the host, and then attaching it to the VM as a secondary disk.
- Boot the VM from your Reflect Rescue Media. Make an ISO for this purpose if you haven't already.
- Follow this KB article
that describes how to restore an image from a Legacy BIOS system such that it will boot in a UEFI environment.
- After running the restore and Fix Boot Problems as described above, also run ReDeploy.