OpenTTD is an OpenSource Port of Transport Tycoon Deluxe
Official OpenTTD Wiki: https://wiki.openttd.org/OpenTTD
This emulator is experimental and can be installed from the experimental menu of the retropie setup script
You will need a keyboard and a mouse - gamepads will not work for this game
When you first start up the game you will be greeted by the following screen:
Download the graphics and then select check online content
If you don't have the original Transport Tycoon Deluxe files you'll want to at the very least download OpenMSX and OpenSFX packs so you have sound effects and music.
Once you've downloaded OpenMSX and OpenSFX you have to enable them in the game options as follows:
Then finally, in order to get your music playing you have to start a new game and turn on the jukebox:
Optionally, you can also download zBase for 32-bit HD graphics and change the Base graphics set in the game options to zBase instead of OpenGFX.
For more information on how to play the game see the Official OpenTTD Wiki: https://wiki.openttd.org/OpenTTD