In the absolute, your pseudo code wouldn't give you the expected result.
THe logic you're using there would make ALL the animations being set one after the other EACH TICK. (So each tick, set the sprite to an animation after the other to the end of the animations stack)
In the end, you would only see the fixed first frame of the first animation. I guess this is not what you want.
Also, you could use some workaround to use a number in the name of your animations.
Ex:
Run1
Run2
Run3 etc...
Meaning that you can set Sprite animation to "Run" & loopindex("getanimations").
But once again, you would have to spread the switching of animations through several ticks, not just in a for loop.
Something more like :
glob var animIndex
Animations name setted as indicated earlier
Sprite: On any animation finished
-> System: Add 1 to animIndex
-> Sprite: set animation to "Run" & animIndex
(opt) -> Sprite: play animation
This should do the trick and doesn't require new ACE.