a number of "fixes" are needed, alas.

the scripts (by design) cannot execute .ini files, so I wish I'd read
the 'portfolio/readme.txt' file earlier.  :-)

to exclude that directory, plus two others, run 'sqlite3 cmpimg.sqlite'
and enter or paste the following:

UPDATE folders SET active = 0 WHERE id IN (
SELECT id
  FROM folders
 WHERE folder = 'animations'
    OR folder = 'portfolio'
    OR folder = 'previews'
);

another oversight was not examining the (extracted) option switches
more closely, two scenes specify no file output which terminates the
process with an unsightly error message.  to remedy:

UPDATE scenes SET active = 0 WHERE id IN (
SELECT id
  FROM scenes
 WHERE scene = 'benchmark'
    OR scene = 'gamma_showcase'
);

and there are a number of animations outside the 'animations' directory
which also need excluding[*]; using '-kf' to identify:

UPDATE scenes SET active = 0 WHERE id IN (
SELECT id
  FROM scenes
 WHERE cliopts LIKE '%kf%'
);

[*] the script can be rewritten to deal with these.  it will need
generating .ini files with 'post_frame_command's to rename the (numbered)
files correctly.  more hindsight..  :-)

and two scenes fail outright, for me, with the 3.8.0-alpha.10064268,
both work fine with '3.7.0.8'.

normmap  - 3.8 line 30 parse error: no normal type given
superel2 - 3.8 line 72 parse error: illegal character 0c in input file

UPDATE scenes SET active = 0 WHERE id IN (
SELECT id
  FROM scenes
 WHERE scene = 'normmap'
    OR scene = 'superel2'
);

after these updates, 'mkcmpimgs.tcl' runs as planned.

# -----------------------------------------------------------------------------

the following should not be necessary, however if 'sh addscenes.sh' did give
you an error, as happened here (a glitch I think/hope), edit the 'addscenes.sh'
file to have tcl source its script from the parent directory,
ie '../addscenes.tcl' and run the shell script from the 'scenes' directory,
ie 'sh ../addscenes.sh'.