Is it possible to configure (say) faders 1 to 10 which carry subs 1-10 with recorded fade times and using Bump as the "Go" button so that if I bring in (say) fader 4 this way then any other active fader between 1 and 10 automatically goes down to

This is technically possible with sACN show control actions. Here's a quick demo: 

However, i do NOT recommend this. Because storing values, that control faders onto faders, that control values, that control faders, that control values, that control faders, (i hope you see where I'm going :D ) isnt a great idea if you want stuff to work predictably.

This is technically possible with sACN show control actions. Here's a quick demo: 

However, i do NOT recommend this. Because storing values, that control faders onto faders, that control values, that control faders, that control values, that control faders, (i hope you see where I'm going :D ) isnt a great idea if you want stuff to work predictably.