Hi Tom,
I tried MdeModulePkg/Universal/EsrtFmpDxe, but booting hanged at selecting Boot option.
I then used, MdeModulePkg/Universal/EsrtDxe/EsrtDxe.inf. There are no issues observed in boot, but, still i am not able to update capsule.
CapsuleApp.efi was complaining that update image failed with status as "Not Ready". Looks like QueryCapsule succeeded, but, UpdateCapsule failed.
Thanks,
Sandeep