Jordan Catalano said: "There’s a “pre-show” (some days, in my experience) but after all the times I’ve seen it, i get there around 20-25 mins before showtime and it’s fine."
Can't speak to how the pre-show is now, but last year, we entered though a side door - they placed a sticker over the phone camera - we went down a dimly hit hall - were given schnapps (this apparently no longer happens at each show) and there were some rooms where cast members wee getting dressed (all in character) - there were, as I recall, at least two different bars where you could purchase drinks (and also swag) and I think about half hour before the start of "the show", there were dancers on the gold bar and on an interior balcony above the bar. We entered the theatre space about fifteen minutes before "show time" and there were dancers on the stage - some who came in from the Gold Bar. Since we had one of the tables (where we were able to order a pretzel - after all, it is Berlin - there's more on the menu) the dancers were right in front of us. 30 minutes should be enough time to get the feel of the "Kit Kat Klub".