Steam [resolved] Starting Tsw 6 Starts Tsw 5 Instead

When I tried to start TSW 6 using a desktop shortcut (pointing to C:\Program Files (x86)\Steam\steamapps\common\Train Sim World 6\WindowsNoEditor\TS2Prototype\Binaries\Win64\TrainSimWorld.exe) it instead launched TSW 5. I then uninstalled TSW 5 but the shortcut still doesn't work, now it just prompts me to install TSW 5. Launching the .exe directly does the same thing.

Launching TSW 6 via Steam launcher or a Steam created shortcut works perfectly fine so it isn't a big issue, but it does mean I can't start TSW 6 with the API enabled (since it requires a shortcut with -HTTPAPI on the end)

Edit: I resolved the issue by creating a file called steam_appid.txt and containing the number 3656800 in C:\Program Files (x86)\Steam\steamapps\common\Train Sim World 6\WindowsNoEditor\TS2Prototype\Binaries\Win64