How did you manage to get the custom recovery installed please? I am having no luck whatsoever. I have followed the install guide to the letter and everything seems to go fine with no errors yet I still have no custom recovery mode when I reboot, With or without the USB Drive. Any ideas?. Entering the recovery mode brings up the standard recovery console.
Try booting to recovery using the connect button instead of issuing a adb reboot recovery command. Mine was going to the stock recovery with adb, but went to custom recovery when using the connect button.
Unplug the unit. Press and hold the connect button on the bottom while plugging it back in. Continue holding for 5 seconds, then release.