To sum up problems of setting up after installing context-lmtx (context
mkiv on my machine is gone, so these are quite pressing questions):

Some were addressed, but I cannot resolve them

1. luametatex: works as intended from within TexShop, but 'command not
found' from terminal $CONTEXTHOME/tex/texmf-osx-64/bin/even after
chmod 755.

What to source?

2. ./luametatex 'no format given'

3. there used to be context --run, now there isn't.