Hi there! Tiled2Unity is no longer in development nor supported. Use SuperTiled2Unity to import Tiled Map Editor maps into your Unity projects instead.
Update: Tiled2Unity is now officially supported on Mac and Linux platforms as a command line utility through Tiled2UnityLite.
In keeping with my decision to keep Tiled2Unity free and choosing the permissive MIT License for it I have recently put all the source up on a public GitHub repository.
Full disclosure: I’m new to GitHub so bear with me if I make a mess of it. I’m a long-timer user of Perforce and Subversion and have been a bit of a dinosaur when it comes to Git.