Introducer doesn't create enough icon sizes

It seems like only 3 icon sizes comes out for Mac builds?
Thats not enough, according to apple:

Are you sure there are 3? As far as I can tell, at the moment only up to 2 different sizes end up inside the generated .icns file: Icon (small) and Icon (large) as you specified them in Introjucer.

Having all 10 sizes in there is a recommendation from Apple, but not a requirement. See here:

it is not a requirement to have a complete set; the system will choose the best representation for sizes and resolutions that you don’t supply. Each icon in the set is a hint to the system as to the best representation to use.

It would be really useful to know whether you actually encountered any problem with your application? (such as an icon not showing correctly etc.)

Because if not, it would probably make sense to leave the two sizes in there: anyway you can specify only two sizes in the Introjucer. We can then leave it to OSX to figure out which to use when. As long as the bigger of the two is 1024x1024, you should be good.