Core Mechanic 2: Return in a Portal Brick
Some players I'm sure skip the instructions and we kind of ran out of time on making one of our core mechanics really intuitive. Since we can't make changes for 20 days I figured the least I can do is write a quick post in case anyone does look for an explanation.

What is a portal brick? A portal returns your ship back to the hangar and opens up the upgrade/select ship menu again.
Returning to the hangar allows your ship to unload all the space men you pick up which gives you points and money. Your ship has a limited capacity of spacemen it can carry so you have to return to the hangar via a portal frequently.
With that money you collect you can upgrade your ships by clicking the green arrows next to their stats.
So if you don't figure out the concept of the portal then you are missing out on a lot of the game!

How do I open a portal? If you run into the portal brick your ship crashes and explodes. It has to be opened first.
To open a portal you have to bounce your balls off it three times. This can be the same ball deflected back at it or three different balls.
Lasers have no effect on portals.
After three bounces the portal open animation starts. The portal isn't "open" until that animation finishes (I did that on purpose...probably a bit too harsh, hehe)