Your Glowforge is designed to operate with the included exhaust hose connected to the outside with a maximum of two 90 degree bends. If you configure your exhaust differently, the Glowforge unit may not be able to expel enough air, and it could cause smoke and fumes to enter the room. Because ventilation is complex and poor ventilation could cause smelly and even dangerous results, we can’t advise on exhaust configurations other than what’s described in the Glowforge Manual.
I’ve moved this thread to Beyond the Manual so the discussion can continue there.