You're on the right track. Your problem is in your reasoning process.

Did you understand and use variables as I outlined to defines which weapon fires?

The reason all your pellets are being destroyed at once is because of the sequencing of your code.

Try

Pellet > On collision with(whatever) > Destroy pellet

Can you PM me with a link to your capx and I'll download it and take a look. I know what the mechanics of your issues is, I'm just not understanding how use the scrolling.

And is it only 2 weapons you need to switch between or do you need more than 2?

Yes you can rename it as long as the "link" you direct to includes the file name in the path as follows:

http://www.yourdomain.com/game.html

You should reach out to — He makes video training courses for C2 and might be able to provide you some direction.

I would create a text box on screen and write the X & Y coordinates to the text box Just to see what it reads when the mouse is off screen. it may be 0, 0 and in that case, you may be able to create a condition that says

Mouse compare X = 0

Mouse compare Y = 0 》do something

Just tried it with a gamepad. Works good but I would include it to fire on the A button and offer the left pad for direction as alternate control options. But that's just me. Offering both let's the player choose.

You tend to get buried on market JS since they frontline their own work it seems. I haven't tried market JS though for a long time and I never tried FGL but have talked to others who have. I would favor FGL, if your making an either or choice but, there is no reason you cant do both.

Do you mean rename the index.html file to something else like game.html? If so, Yes.

Try creating an invisible small sprite and pin it to the mouse every tick at position mouse.x, mouse.y and then create the condition as :

Sprite > Is OnScreen (x) > Do something ( x being inverted )

Look right in Construct 2's sample project examples that come packaged with it. I'm almost positive there's a demo in there that shows what you want...

When you set them as global in the properties dialog, they are global across all layouts.

I downloaded. It is a bit confusing. I know your new. Give me a day or 2.

In the properties dialog box is "Default Controls".

However you decide to switch between controlling player sprites, set the current one to use "default controls" and deactivate the one your switching from..

Use a global variable (Set_Player). Then make a few statements.

System > Set_Player = "Player_1" > Player_1 > Stop Ignoring Input

.........................................................> Player_2 > Start Ignoring Input

.........................................................> Player_3 > Start Ignoring Input

System > Set_Player = "Player_2" > Player_1 > Start Ignoring Input

.........................................................> Player_2 > Stop Ignoring Input

.........................................................> Player_3 > Start Ignoring Input

System > Set_Player = "Player_3" > Player_1 > Start Ignoring Input

.........................................................> Player_2 > Start Ignoring Input

.........................................................> Player_3 > Stop Ignoring Input

Depending on the variable value, controls will default to the selected player sprite.

Hope this helps.