Drag and Drop - Simple

Hey there.

I am wanting some 'drag and drop' functionality for a module I am creating.

I have tried a few tutorials but I can't quite get my head around it. Plus, the tutorials that are available seem to be more focused around not using the timeline and more using pure code. I would rather use the timeline + Instance names etc.

Essentially I have 3 drag objects. They need to be placed in the correct position named box1, box2, box3. Once the user has all 3 drag objects correctly in the boxes, a button appears to move onto the next stage.

I've uploaded my project here.

I feel like I'm not using the full power of Adobe Animate - if you see some things that I am doing wrong please also let me know!

I am using video imported from another program, and then I use z-index:-1 on the dom overlay once the program has been exported (so that the buttons become interactive, otherwise they are behind the video).

Thanks for your time and in helping me out here.