We will need a little more.. a link to your capx in a dropbox folder would help a lot (put spaces in the html link here so it shows as text since you won't have permission to post actual link yet). Or explain what events/actions you are using.

In your spawn condition randomize the apple placement and check for overlap before spawning (if not overlapping).

Have this placement repeat until successful. Unless you have a ton of stuff on screen it should work fine.

If you find the apple is too close to the snake/body/head then also condition distance is greater than distance from head.x head.y body.x body.y +50.. etc, etc

If you have the sprites for the bloody ground overlay then you can just spawn them from the hit object when needed.. you can do same thing with exploded giblets and parts if they are separate smaller sprites by randomizing their distance and direction (angle) from the exploded objects.x and .y...

paint.net or good ole MS Paint

Start by making your title more specific... your question should have been your title.

I am assuming your level is larger than your camera view and you want the HUD to stay with player as he moves around?

"The HUD always stays the same place on the screen. If we have some interface objects, we don't want them to scroll away as the player walks around - they should stay on the screen. By default, layers scroll. To keep them on the screen, we can use the layer Parallax setting. Parallax allows different layers to scroll at different rates for a sort of semi-3D effect. If we set the parallax to zero, though, the layer won't scroll at all - ideal for a HUD."

from: https://www.scirra.com/tutorials/37/beginners-guide-to-construct-2/page-7

Vague questions get snowballed answers . XD

I think you can put the objects into a container and it will only pick the family member is the container that is hit.. its an easy way to "pick" instances.. read manual on containers.

You could always hack it.. make an invisible sprite the size of the screen (make it follow camera if scene is large) and use Is-overlapping sprite to condition out ones that are off-scene.. there are more legit ways to do this but I like hacks.

you did say "field"

You do text boxes the same way.. under Size & Position in the TextBox actions is a set text box size action.

Your saying if one instance is large and explodes and another smaller instance is hit and explodes then the first instances explosion is set to the scale of the latter?

This sounds like a "picking" issue.

Make sure you condition out old sprite1 that are already exploding...

maybe use an instance variable isExploding=0 then set to isExploding=1 at start of exploding animation, then use isExploding=0 to condition out old ones when creating new explosions...

Glad you solved your issue. Let me point out why it was happening which might help you with other Construct2 instance handling.

Construct2 relies on instances (objects of the same type) being "picked" by conditions so it knows exactly which object you want manipulated.

If you don't let it know which object to pick it will pick all that apply and you will get "fish schooling" behavior.

I highly recommend searching for object picking in the Construct2 manual, very handy info.

Each time you told your car to change colors it changed them all since they are all car_to_choose_2.

Your fix method worked because it basically turned off all but new instances.

Another method would be make an instance variable in car_to_choose_2 called something like colorChoosen=0 and then when it is colored change it to 1 (colorChoosen=1) and condition to colorChoosen=0 (or not (X) colorChoosen=1) in your color change event.

[Condition On created car_to_change_2 colorChoosen=0]

action - car_to_choose_2 set frame random(0,3)

action - colorChoosen=1

You will need an instance variable in the sprite1 for CurrentSize=0, then set this variable to the scale of sprite1 when it is hit.

Then all you need to do in your explosion spawn event is set the explosion size to CurrentSize... but make sure you haven't destroyed Sprite1 since your using an instance variable... just make sprite1 invisible while explosion happens and then destroy both sprite1 and explosion at same time... or use a global variable.. but if you have lots of sprite1-# you would need as many global variables if two would ever be destroyed at one time...