Will not launch v17 on Fire Stick

I’ve installed v17 on Fire Stick 1st Gen but it crashes upon opening. I’ve tried the usual tricks (Force stop, cleared cache etc). I’ve even restored the Fire stick to Factory defaults but when trying to run Kodi, I get the “Preparing for first time use” screen then it goes grey or black and back to the normal Amazon screen. I’ve tried Beta 7 and all the RCs. The latest nightly even shows up as RC3 but does not load. I have installed via adb from Windows and I’ve also tried installing from ES Explorer. I’m not new to this but I really can’t see what the problem is. 16.1 Jarvis works no problem so I just keep reverting back to that but would like v17 to run.
Can you help? Confused