All The World's A Stage is bugged.

[_-Dave-_]

At the part : Investigate Backstage, the door with the Red Star cant be opened.
I also didn't get to talk to the Ticket guy, he just repeats that the star has not arrived (but I didn't get any conversation, hes just stuck saying this.

This really sucks cause I wanted the Engineer Armor set for my character. Now I'm locked out of it.

[Mooman]

I think, but not 100%, you need to find and wear a clown costume before knocking on the door.