trying to offer help
what exactly is your problem mentioned about icon files?
are they toolbar icons or what?
There exist a few diff ways to deal with this...
Also you might want to know about this:
https://pnggauntlet.com/
It is free and works great in that you can drop the whole folder of the theme png files onto it and let them compress... results in faster functioning and smaller theme size... [often by a lot!]
I'll wait to hear more about the 'problem' with icons