If you open up Extrude 8 they have defined the areas of the sketch that are extruded by selecting the areas they want to extrude under "Profiles". Looks like changing dimensions causes it to lose the reference and it needs to be re-selected.
Other than that, your ribs look like they aren't linked to another dimension and when you changed the size of the area they are now broken because they are too short.
But for real thanks! I'll take a look when I sit back down at my windows computer. As far as I know, I didn't change any of the dimensions that would have affected the fins like that... Maybe I changed the wrong parameter.