When installing on 64 bit versions of Windows, Trebuchet installs into the Program Files folder. However, it is a 32 bit application, so it belongs in the Program Files (x86) folder.
After install Windows prompts the user to re-install the program "with the correct settings."
After this is completed, Trebuchet will not launch because its shortcut points to tclkit.exe in Program Files\tclkit which no longer exists.
As such, the application cannot launch.