Event 71 is setting the player's y vector to a small value all the time when you're not jumping. So the player is constantly falling and never actually on the ground.
I've checked that and as far as the platform behaviour is concerned, when the character is grounded it "is on floor"
And if you're using x for both falling through and jumping you'd want to set it up so you don't jump while down arrow is down.ot really an option. Being able to jump (either from standing or crouch) and fall through platforms using the same button is what I'm aiming for. It's also pretty standard control scheme layout.
Though you did give me an idea. I moved the events that pull the player down up to an "else" of 'player is on floor' removing them from the "jumping" group, and did this:
+Player.is on floor
+Keyboard.Down arrow is down
+Player.Is overlapping "platform" at offset (0,2)
-System.Set group "Jumping" Deactivated
++Keyboard.On X pressed
--Player.Fall down through jump-thru
--System.Wait 0.2 seconds
--System.Set group "Jumping" Activated
(In case the way I write events is confusing.
+ = condition, - action, ++ = sub event condition, -- = sub event action)
So what i'm doing is that while I'm standing on a platform and pressing down jumping is disabled, instead of disabling it when i'm pressing dow, period. I then reactivate jumping shortly after to allow midair jumps after falling through.
Now, whil this works, it's not without problems either. If I hold down the key after falling through, the player will start moving upwards as the jumping group is reactivated. Currently trying to fix. I'll see about getting a new capx up soon.