There seems to be a problem where you can't enter an expression. For example, if I enter
1000, 2, 2700, 100, 500, 1,255, 10, 5000, 7, 0,0, 500, 2, 5000, 1
in the expression box and press enter to save it and drag the action, the action just stays at start color flow with expression 0 and that windows beep noise plays.