I went through the steps using BCA to create my USB installer and partition my drive. Everything went fine, ended up messing up after a successful install and decided to wipe the partition and start again.
Here's where I went wrong. Instead of using BCA to wipe the Windows install, I did it manually through Disk Utility. I then created a new ExFAT partition in DU and went about the install process again. However, since that point I have had 2 Windows partitions show in the Boot Loader, the old non-existent one and the new working one.
Any thoughts ? I don't really want to risk losing my new windows partition but if I don't have to.
If it helps, when I try and quickly reboot into windows with BootChamp (3rd party app) it gives me this message which could be of use:
Thanks in advance.
EDIT: Clicking on the second/"old" Windows icon in the Boot Loader screen takes me to a Windows 10 Recovery screen that tells me a required device isn't connected or cannot be accessed. Interesting. I mounted the EFI disk with
diskutil mount /dev/disk0s1/, went into the Microsoft folder and backed up and deleted the "Recovery" folder that was in there. Unmounted with diskutil again, rebooted into Boot Loader and it was still there. So there goes that plan.