Finally got around to designing a custom PCB for the gas sensor. I am entirely new to using Fritzing so I decided to simply use the Arduino Nano as it was without breaking out the chip, supply etc. This isn't the best use of space but should make this super easy for anyone to replicate.
The PCB design went really quickly and I was able to export the design files in an hour or so:
Off I went to the OSH Park website to use the credit I received from an early bird prize in the Hackaday 2015 contest. The PCB's were really cheap and I ordered- but 5 minutes later I found a serious error in the design- so I re-ordered again :)
Version 2.0 looks promising and once I have verified it works I will post all the design files so everyone can create their own version. Super happy with this project and loving that it has been well received with the open source and electronics community.