From the manual:

Mobile limitations

Safari on iOS and Chrome for Android share a limitation in playing music. While sound effects can be played at any time, music is only allowed to start playing when the user touches the screen. This is a limitation in the browsers themselves. As a result, if you play music on the start of layout, you may find in these browsers it does not actually start until the next touch.

Safari on iOS has a further limitation that no audio can play at all until the first touch. In other words, audio starts off muted and the first touch unmutes audio playback.

Usually you do not need to handle this in your events. If you try to play sound or music on 'start of layout', the audio object will automatically queue it up for playback the next time the user touches the screen. However you should be aware of this when designing your game. If the first touch changes layout or stops the music, then the music may never be heard. You may want to start playback then encourage the user to touch the screen with a 'Play' icon or something similar.

Tried the tutorial section?

https://www.scirra.com/tutorials/311/level-select

on touch create a sprite

if sprite.x > player.x - player simulate platform pressing right

You are probably looking for the simulate control action..

If you add the platform behaviour these should be in your possible actions

so on >> pushed - playerbox simulate control right..

or something like that..

There is the disable collisions action?

I would try using lerp (linear interpolation) for this

something like:

every tick player set position x=lerp(player.x,mouse.x,0.5) y=lerp(player.y,mouse.y,0.5)

the issue with the walls could come from the bullet missing the collisions due to speed

Wouldn't that just be a matter of adding the condition if sprite.y<0

and adding actions for when that is not the case?

Just add a condition

target animation is not broke

should be fine..

Make a variable ActionIsBusy

set it to no

on action - set to yes

on acyion finished set to no

if actionisbusy =no - start action

Did you try something like this?

set the origin at the top and set height to viewportbottom-sprite.y

Would working with blendmodes help in "masking" part of the screen?

Wouldn't using a boolean variable be much easier?

on textbutton clicked - toggle variable On

• if variable On is true - set text to "Bonus chest; On"
• if variable On is false - set text to "Bonus chest; Off"

You could also use a numeric variable

on button clicked set variable: 1-variable

that way you have the variable toggle between 1 and 0 too..