Slight caveat with using Cocrea for widescreen, i think you need written permission from SFSG to post Incredibox content on that site.
Also, about the 6 in each category thing, the way I did it was taking a template with 5 bonuses and modding it from there, like you add 2 more to the "Repeat 9" part for 2 more on that row. You can also get rid of the fifth bonus unless you still want it.
I use Scratch for Incredibox modding because it's the easiest to work with and keep your projects up.