See 4.2 in the reademe.txt
If you put them in your shared or personal directory then they will be found by any installation you make. Using the online content download button you can download newer versions of them when they become available.
section 4.2 in the readme.txt of r18724 wrote:
Code:
4.2) OpenTTD directories
---- -------------------------------
The TTD artwork files listed in the section 4.1 "(Required) 3rd party files"
can be placed in a few different locations:
1. The current working directory (from where you started OpenTTD)
2. Your personal directory
Windows: C:\Documents and Settings\<username>\My Documents\OpenTTD
Mac OSX: ~/Documents/OpenTTD
Linux: ~/.openttd
3. The shared directory
Windows: C:\Documents and Settings\All Users\Documents\OpenTTD
Mac OSX: /Library/Application Support/OpenTTD
Linux: not available
4. The binary directory (where the OpenTTD executable is)
Windows: C:\Program Files\OpenTTD
Linux: /usr/games
5. The installation directory (Linux only)
Linux: /usr/share/games/openttd
6. The application bundle (Mac OSX only)
It includes the OpenTTD files (grf+lng) and it will work as long as they aren't touched
Notes:
- Linux in the previous list means .deb, but most paths should be similar for others.
- The previous search order is also used for NewGRFs and openttd.cfg.
- If openttd.cfg is not found, then it will be created using the 2, 4, 1, 3, 5 order.
- Savegames will be relative to the config file only if there is no save/
directory in paths with higher priority than the config file path, but
autosaves and screenshots will always be relative to the config file.
The preferred setup:
Place 3rd party files in shared directory (or in personal directory if you don't
have write access on shared directory) and have your openttd.cfg config file in
personal directory (where the game will then also place savegames and screenshots).