Deactivate VSync in the game options and set the frame rate to "Unlimited".

Open the NVidia control panel and add the game.exe (TTOL.exe) to the application list. Once added, set VSync in the control panel for this application to "ON". Close the panel.

Open the Steam library, find the game, right-click and open the properties. Under "launch parameter" add the line "-window-mode exclusive" without quotation marks. Close the window and start the game. It should run smooth now with activated VSync.