I`m not sure about using cacoon.io , couze I use Cardova in Intel XDK.
Of course you dont have to download the software ,Intel XDK
But when your HTML (Construct 2) after export to HTML.. try play it by double click the index...
For me after I export the game to HTML in a folder ,it will (index) will appear with chrome icon
Then you can try to format it using the cacoon.io to .apk...
If in "Index work well, and in .apk dont ...
You may need a new to upgade only related things(not recommended). Sorry It`s been awhile after my last . apk game so I kinda dont remember it well