Lots of variables here, and lots of good advice above. My 2 cents... To prove that your TMCC works, can you borrow a Lionel engine from a friend and try running it with your setup? If it works, then you'll know that your TMCC system is functional and connected properly.
Another thought - make sure that you are using the correct power source for your TMCC. Although it looks like a common wall wart, it's not.