Have you tried the RESET button?
The links to the skytex firmware have changed since i d/loaded the firmware last.
Seems the new loader/upgrader is looking for a img file but the skytex loader/upgrader is looking for a bin file instead.
Heres what i used for the primer/skytex firmware, RK28DM
I've uploaded it for you to download on the link below and it will load the .img file which you should have.
Rk28DM
2shared - download RK28DM_Setup.zip