Doesn't require direct access to internet from your Dreambox.
(Some people tends to be blind and doesn't see the dot at the line start.There is dot space slash at the line start!)
If it ends with an "Installation error", then the installation file is corrupted (often when you open this file with a text editor).
The Drtic plugin looks for subtitles in the /var/tuxobx/Drtic/tit directory. They should have .dtc extension.
For Drtic's activation press the yellow (in some images) button on your RC. The Drtic plugin could be activated from Plugin menu on some images. Select Drtic from the list and press OK. You should upload subtitles to your Dreambox (otherwise you'll get "Can't open file with subtitles!" message). You can use any ftp client (classic commandline ftp client, ncftp, Total Commander, FileZilla, etc.), or jDrtic with '-s' option.
Drtic's help could be activated by HELP button on your RC when subtitles are paused. Press OK to START/PAUSE subtitles, LAME to quit. Indicators are in the upper right corner. The first one is PLAY/PAUSE indicator. The next one is brightness indicator, followed by zoom inidcator. You can set elapsed time of the programme you're watching - just start typing numbers.
More informations and jDrtic - the subtitles convertor you can find at Drtic's homepage.