Yes, the size of the Cogol program is a decent estimate of the Kolmogorov complexity of the Tetris program. However, you also have to account for the size of the computer (including the massive RAM bank) - the Cogol program just encodes the Tetris program.
Naturally, no general-purpose compression scheme (or even a somewhat-specific-purpose scheme like MacroCell) is going to come close to the Kolmogorov complexity. We could come up with a custom compression scheme and write a compressor and decompressor, but give us a break - we built a computer! :P