Can you explain in more detail? I JUST did the update about 20 minutes ago and it worked fine to get me into gw 6.3. I was at a cafe hotspot and had a signal BUT it kept failing. Had to move closer to the source (was outside the restaurant at first) and then it worked.
I also had NO wifi/internet setting setup on the REALnand side. I only setup wifi connections once I was in the emunand side (so GW 4.4.0 for me) and went into system setting/internet settings, and turned on wifi, had it find a connection point (the restaurant wifi) connected, clicked to the 3rd page in the settings where it says "update system" and had it download and automatically apply 6.3 to the EMUnand side.
When I went back and forth, I saw the REALnand side did NOT have any wifi connections saved, but the EMUnand side still showed a saved connection (and I had a bunch of footstep counts for whatever reason) :-P
I did everything the same as you and I went back to REALnand and deleted my connection there, Then jumped into GW mode, confirmed the version GW 4.5xxx and simply went straight to update... its strange