Is there a working emulator for thrillville off the rails ds

Try for your self. There are 2 DS emulators who are the best at present. 1) No$gba 2) iDeaS You can google search them. Please post here if it worked for you. If the game gives save error in No$gba, then follow steps: 1) Open No$gba 2) Go to configure> nds cartridge backup media 3) Choose save type to EEPROM 512kb 4) save options. 5) Restart your game.