You will smell like a kipper. Take the flue out throught the roof or wall using 45deg bends 90deg slows down the flow make sure you have 2" clear all around any combustable material.
As long as it draws ok you should be ok, i would imagine in a garage there would be enough gaps to allow fresh air to come in. Sometimes in modern houses with double glazing and draught excluder the fire simply can't draw in enough fresh air to allow combustion so thats when you get smoke coming into your living room! Be careful with your choice of wood too, make sure its seasoned (dry) and good burning. I usually get the fire going with some Pine as it is easy to light and burns hot then switch to Oak/Ash or beech as they burn well for longer. Nice stove by the way, they are coming back in fasion bigtime!!
I only use mine outside during summer months, wouldn't recommend having it burning with the door closed unless the flue is going outside, even burning wood produces carbon monoxide which is tasteless smell less gas that is poisonous so if you use it in a confined space get yourself a carbon monoxide detector.