1. Dont work sell button. No cash refunded.
2. When helicopter pad is builded no helicopter at all. So the price of helicopter is 1500 (pad) + 1500 (helicopter itself). 3000$ is too much. Moreover, this way helicopter's rush is impossible.
3. Cannot change speed of a game at all. It always play on maximum. With this speed noone can defend his base against engineers+APC on early stage of a game.
Attack power of units greatly changed comparably with original C&C.