Justdave, the second step bonus can be claimed when reached level 5.
The promotion scheme in on the first post of the thread.
You don't need "btc" for reach level 100, you need to play the game correctly and the necessary time for upgrade your buildings/production.
Ofcourse you can speed up the process a little buyng gold, but gold can help you in obtaining resource, not in advancing in the game where your strategy and management is still the most important thing.