sorry, more strings that looks weird:

#: ../savers/slideshow.c:55
msgid "Color to use for images background"

maybe it is bacground images ?


#: ../savers/slideshow.c:55
msgid "\"#rrggbb\""

It is as an example of how people have to put the color in the entry or it's the entry itself, because if it's the second I don't thing that it is a good idea to make it translatable, rather it would make sense to get this color from the current theme

#: ../src/gnome-screensaver-dialog.c:63
msgid "MESSAGE"

with this you pretend that translators have to translated it or we have to write a message that will show on the dialog (looking at the line above gives me that though)

that's all

just another one more:

#: ../src/gnome-screensaver-command.c:78
msgid ""
"Inhibit the screensaver from activating.  Command blocks while inhibit is "
"active."

-- the second phrase is correct? Maybe is something like "Cmommands are blocked while inhibit is active" ??

For msgid "MAX_IMAGES" and msgid "MESSAGE": these are the command line arguments of the given programs. Capitalization always means that they should be supplied by the user. To see these messages "in action", you should use something like this: (given that you have a fresh and working jhbuild gnome somewhere in /opt :))

devel@gabor-laptop:/home/gabor$ LANG=C /opt/gnome/libexec/gnome-screensaver-dialog --help

Usage:
  gnome-screensaver-dialog [OPTION...]

Help Options:
  -?, --help                 Show help options
  --help-all                 Show all help options
  --help-gtk                 Show GTK+ Options

Application Options:
  --verbose                  Show debugging output
  --version                  Version of this application
  --enable-logout            Show the logout button
  --logout-command           Command to invoke from the logout button
  --enable-switch            Show the switch user button
  --away-message=MESSAGE     Message to show in the dialog
  --display=DISPLAY          X display to use

should be closed by now?

OK.