The controls to move are I,J,K,L, and to pump is shift+J/L The total bar, i.e. red plus yellow, represents the minimum amount of time an animation cycle is allowed to take.
Press A or S to decrease or increase the red time and Z or X to decrease or increase the total time. Default values are 20 ms for the former and 100 ms for the latter, which feel OK on a Sun SPARCstation 4, but you may need to tweak and tune them a bit to make the game run optimally smooth on your machine -- especially if it has a slow processor.