Further update …..
Updating RM to v4.04 gave a fatal error against the MaxButtons Plugin.
I could not continue down the road of v4 upgrade.
Investigated further and the reversion problem is due to PDF Poster Plugin.
So …. deactivated PDF Poster allowed me to revert to v3 (reactivate PDF Poster afterwards is fine).
Personally, I am happy to stay on v3.
You and or other users may wish to investigate further to avoid the problems going any further.
Thanks again
It’s OK – I’ve changed my priorities around to explore v4 and make it work for me (I use it on multiple sites), so revert is not needed (by me) any more. Many thanks for your support though.
That’s precisely what I’ve done, multiple times …. and it remains as v4 🙁