MakerBot Print is our newest print-prepration software, which supports native CAD files and STL assemblies,
allows you to interact with all your printers via the Cloud, and many other exciting new features.
If you turn the water supply line upside-down (as in the STL I uploaded), most of the structure builds upwards, without the need for supports. The only exception is spanning the width of the tube itself for the span that goes horizontally - but that's only a span of about 8mm or so, with structure on both sides for support. At least on my printer (an i3 MK3) the plastic was easily suspended across the gap until it hardened.