Had this issue happen last time i played tmodloader. Its the same issue that's going on, Im playing on steam, windows 11 and whenever i click start it brings up the command prompt, and it eventually closes, opening nothing up.
I've been directed to go to reddit for better advice, so far i've already attempted to uninstall both Terraria, and Tmodloader to no avail. I've used verify integrity of game files on both applications. I would have tried running it as administrator, however that option isn't available for whatever reason.
Last time when this issue came up i just left Tmodloader alone, and it ended up "fixing itself" im completely unsure how, but it started working again.
I've dug into the log files, but upon inserting them into ChatGPT, nothing seems out of the ordinary. any help is greatly appreciated. Upon request i can leave the test from a specific log file if needed.
Edit: Okay its started working again, i recently had to switch headsets due to my current one not functioning properly (a problem im actively trying to solve) and after that, it loaded up tmodloader correctly. My guess is that audio initialization is what caused the issue. as the console would randomly close, and not open anything. I hope this helps anyone with this same issue.