This game is really, really, really well polished. However, I couldn't find any portals to advance the game after 10 minutes of playing. Any pointers I'm missing on how to proceed, or is it at random?
completely random. You basically have to look around for them. They always spawn in a tight area around you though, so stopping and just looking around should help.
There is something very strange about the bullets in the bossfight though. It didn't work in the build, but in unity itself it did. I have no clue what happened, sadly..
Edit: Did a quick fix and uploaded a new working version.