When I originally installed devuan-alpha for evaluation, I did so only
for the basic cli-only system, and only recently added a GUI.

1] The slim greeter theme is inconsistent with the rest of the devuan
theme, even though all the files are in place to make it consistent.

1.1] How to do it on your own:

# aa="/usr/share/slim/themes/devuan-boruch" ; mkdir $aa; cd $aa
# cp ../devuan/slim.theme ./
# cp /usr/share/images/desktop-base/your-way_purpy-wide-small.png \
     ./background.png
# cp background.png panel.png

In the file 'slim.theme', change background_style to 'stretch'. You'll
probably then want to adjust the locations that different things print
out, eg. 'input_name_x 121', 'input_name_y 150', 'username_x 121'
'username_y 120', 'password_x 121', 'password_y 120'. I also changed all
the colors to #222222 (its a free country, that way).

2] The slimlock configuration file was not present.

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