RB2011 failed from upgrade from 5.20 to 6.2 RB2011

I upgraded from 5.20 to 6.2 on a RB2011 and for a second it worked, then was unresponsive to anything on any port. This router has been working on a system for a year.

I Net Installed back to 5.20 and it seemed to ONLY work after reset. I could do anything I wanted on it and it worked UNTIL I rebooted. After Reboot it becomes completely unresponsive again.

It now does this and nothing can break it of this weird behavior. It works perfectly after fact restore ( pressing and holding the reset ). I can config and all works UNTIL reboot and then it locks up completely.

I Net installed 6.2 and that seems to be happy now. Net installing back to 5.x does not work. Produces symptoms above.