fatal error when trying start ToT

whenever i try to start a new game with ToT, all i get is this,
i have combed through every last line of rules.txt and found no problems,
the game launches but if i try to select start new game, customize world ect., the game crashes and gives me this,

I've had the same problem. It turned out that there were a few commas that I had overlooked in the rules.txt. I don't doubt that you have checked it, but it's incredible how easy it is to miss a missing comma.

What TP said. Try line 32 (unit 31) in the @UNITS table. Check also the spelling of the prerequisite and obsolescence techs. Remember, they're case sensitive.

Is @UNITS a guess or have you deciphered the code to discern between @UNITS and @CIVILIZE, @IMPROVEMENTS, etc?

Half and half, I suppose. You can generate these error messages deliberately. In a minute or so, you'd have figured out that module 3 is consistent with a rules.txt file error, and that the negative error numbers correspond to various tables. A few examples:

-4 @CIVILIZE or @ENDWONDER
-5 @IMPROVE
-6 @UNITS
-7 @TERRAIN

The data values indicate the position in the table where the error was generated. That's how I hunt down these types of errors. So far it's worked every time.