@uberiain at this point, when I am uninstall the old XCP-ng center software, and install the new msi, I just realized the xcp-ng keeps the settings file in Roaming folder. (C:\Users\user\AppData\Roaming\XCP-ng)
When I deleted it I could re-register the servers.
It seams migration back to new SR is very very slow. in the 1 - 2 hr mark when the initial migration with converting vhd to qcow2 was quicker in the 20 - 40 min mark.