Baseline (Widescreen) Solution & Issues
I just downloaded the demo for this game from CodeMasters and it appears that you can get it running in 1280x720 widescreen mode.
Even though this resolution does not appear in its built in list, you can go to its main root directory and find a file called:
pchardwareconfig.ini
Edit this file and down near the end of the list you will find the height and width of the screen settings. I entered 1280 and 720 and then saved it and ran the game and it was playing it at that resolution (the projector reported it as 720p resolution).
Racer_S did release a cam hack, which is available below.
Ultra/Super-Wide (21:9/32:9) Specific Solution & Issues
Eyefinity / Surround Specific Solution & Issues
4k UHD Specific Solution & Issues