it does work actually. i do

own_speed = 100.0/own_frame_length;
ent_animate(my, newlabel, animP, ANM_CYCLE);
animP += own_step * speed * time_step;
animP %= 100;

where own_frame_length is the num of frames of each piece of animation, this normalises all animation speeds. So i just need to store the lengths in an array for each animation .

var amin_A_lengths[3] = {12, 24, 8}; // start, loop, end

great!