I have a basement studio and I did battle with flue reversal. It's not an overly cautious observation, it's real. It was easy enough to fix, just be sure that you plan for it. It was easier for me to build an enclosure around my furnace and hot water heater than it was for me to enclose the larger studio area, so that's how I handled it.
My propane tank is outside, I followed DeAnne's thread on how to plumb it into the basement. I still go outside and disconnect the tank when I'm not torching. I don't want to risk a leak when we're not home or worse yet...sleeping.
The make-up air wasn't an issue for me because we have 4 windows in the basement. Setting up ventilation was easier too because I replaced the glass in one of the windows with wood and cut a hole in the wood for my ducting to the outside. I'm sorry I don't have any pictures of this. No part of my studio would be considered pretty so I've never bothered.
The safety exit thing IS still an issue for me. I positioned my workbench so that there is nothing between myself and the only exit, but we have no egress windows and only one way out. I'm thinking that unless concrete floors burn, I'd be able to get out. I have a fire extinguisher. If the fire is bigger than that can handle...I'm gonna run.
I have a dehumidifier down there, because we always have. It would make me nervous to have my expensive equipment down there if it was damp.
Before I moved into the basement I was working in an enclosed back porch. No heat, no air conditioning. There were only about 8 weeks out of the whole year when I wasn't freezing or sweating to death. In the basement everything is a lot more temperate. LOL In the summer it feels cooler than outside, and in the winter I'm actually comfortable. I would so NOT go back to the porch. I'd build a brand new free standing studio before I'd suffer again.
I love my scary basement studio. It keeps the tourists down to a minimum too.