Vienna T3 is like Munich--one building but different floors. Non-Schengen departures are on the top (third) floor which are G gates and Schengen departures are on the first floor which are F gates. Lounges are on the middle floor at the root of the terminal building. Non-Schengen gate and bus arrivals feed into the middle floor of the terminal for passport control. Schengen gate arrivals are directly onto the first floor (F) and Schengen tarmac/bus arrivals feed into F just at the root of the terminal. In any case, everything is clearly signposted.