In such situations, and as much as Elation Support DOES read this forum, this is a situation where you just gotta pick up the phone and call them up.
Suggestion for ALL:
Whenever doing a firmware upgrade, please have as much as possible the following options:
1: UPS battery back-up for all involved elements, generator or other hot-switching solutions to ensure no disruption in power.
Read the instructions TWICE before even trying a firmware update.
First read: familiarize
Second read: Take notes
Print, write notes, make checklist and DO NOT SKIP steps.
Finally, you may attempt a firmware udpate, using the checklist. Check each step as you go.
Some equipment, and I'm not naming names, makes or models(but I am dealing with NON-Lighting gear) often has a recovery mode in the case of firmware upload and screw-ups, as well as fail-over recovery methods in the event of total firmware disaster with a very bare bones OS that is only sufficient for getting firmware into the unit.
When I upgraded my analog audio console's firmware, I had a UPS on the console and the laptop running on a freshly charged battery. No chances were taken. It went fine. Took less than 3 minutes.