two types i'm talking about specifically:

forward + forward (double tap to do the input)

down + forward + punch (quarter-circle forward + punch / fireball motion)

You should to share the project.
What are those commands? buttons on screen?

Oumuamua wrote:

You should to share the project.
What are those commands? buttons on screen?

no, they aren't buttons on screen. i'm talking about keyboard inputs.

Here’s how to detect double-taps.

when this sprite clicked

set [SpriteClicked v] to [true]

broadcast [SecondTap v]

when I receive [SecondTap v]

broadcast [Command v]

Use the “if touching mouse-pointer” to detect the second tap. Hope this helps!

Double tap involves a time limit between keystrokes.
Since you have different key combinations i´d say that reset timer to measure time could be problematic.
I recommed you to create some variable e.g. for foward+foward one var, lets say “first foward” at first keystoke set to timer so you can check, when you press the key again, if timer minus “first foward” is less than 0.1 validates the double tap.
I hope you understand what i mean.