my capx is 21MB. I'm pretty sure it will be around 40MB at the very least when exported though.
As for loading, it said on Ashley's article (number 4) that it will still show C2's default loader until it downloads completely the custom loader.
Problem is, my custom loader is just a blank layout with a single text object. I doubt that text object is taking long to load.
My custom loader only shows when C2 loads the whole project, which defeats the very purpose of a custom loader layout.