Hover state overriding selected button state

Hi all

I've been having trouble replicating a set of buttons I somehow created in a SL file I created ages ago in a new SL file. The buttons in the original SL file work perfectly - I'm not sure how I did it but I have it so that the selected state (a green tick) overlaps the hover state (a greyed out box).

I imported the original SL slide into my new SL file but the buttons don't behave in the same way after import - ie. in the new SL file, the hover state overlaps the selected state when I hover over a button after clicking.

I've reviewed a few discussion articles but can't find an answer that works for me. I tried the step in TomKulmann's video on this form article, but it's just not working for me when I take those steps: My hover states are overriding my selected states | Articulate - Community

Can anyone advise what I need to do in the new file (attached) to make the selected state layer over the hover state (and get it to behave like the buttons in the original file attached)? 

I've attached both the original SL file (which is where the states are 'working' and my new SL file (where the hover state is covering the selected state.

Thanks in advance for your help! :-)