Hi,
friend and I had the famous problem of updating being stuck for several hours without budging. We tried two different laptops, one running Win7 in VM, other WinXP with older version of Garmin tool for update (I forgot the name). Both demonstrated same behavior.
The problem seemed to be in my WLAN, which I know is quite bad and packet losses are often. When we switched to LAN, that is plugged laptop with cable, download went without any issues from both machines.
The most probable reason why only handful users experience this is that usually people have stable internet connections.
I would answer in some opened thread, but all I found seem to be closed.
Thumbs down on Garmin for providing network apps without resiliency to packet losses. Hopefully, they will have test with such scenario someday.