hi chooched! sorry for my late response,i was going to suggest some basic connectivity checks,as alot of times bad usb cables,things running on the PC,and other small issues can interfere with the image flash,even tho it may look successful.
thanks for sharing your finding,as ive never experienced that on an htc phone before and would not have thot to have you try it
im sure lots of folks may find it useful
just holler if yuo have any more questions