I got LMTX running on macOS Catalina.  I followed the directions here
<https://wiki.contextgarden.net/Installing_ConTeXt_LMTX_on_MacOS> for
versions prior to Catalina, including authorizing the mtxrun script through
Security & Privacy General tab.  The first run of install.sh stopped with
the errors:

cp: cannot stat
'/Users/tkb/context-osx-64/tex/texmf-context/scripts/context/lua/mtxrun.lua':
No such file or directory
cp: cannot stat
'/Users/tkb/context-osx-64/tex/texmf-context/scripts/context/lua/mtx-install.lua':
No such file or directory


So I ran install.sh again.  This time it said a bunch of things were
missing and downloaded them.  It seemed to finish ok, so I ran context on
my document and it produced a PDF!  (The ConTexT with TeXLive 2018 and
TeXLive 2019 both died on this document with different unhelpful errors, by
the way.)

Both LMTX and TeXLive 2019 ran 5 to 10 times slower than TeXLive 2018, and
both complain about "fuzzy paragraphs" with a list of U+XXXX codepoints.
What's that mean?

However, the PDF has unwanted whitespace in many areas.

   - It has unwanted whitespace between the entries in the Table of
   Contents.
   - It has unwanted whitespace before and after section headings, despite
   me having "before={},after={}" in the \setuphead commands for all the
   levels of sections.
   - And it had a large unwanted white space between paragraphs until I
   \setupwhitespace[none]. I'd prefer a little bit of white space between
   paragraphs, but I tried \setupwhitespace[0.5ex] and
   \definemeasure[between][0.25ex] with \setupwhitespace[\measure{between}],
   and \setupwhitespace[5pt] but all those went back to way too much white
   space between paragraphs.

Any ideas?
-- 
T. Kurt Bond, tkurtbond@gmail.com