My Aug 2013 RRP (melzi) Huxley needs some long service maintenance, so I decided to build another Huxley as I did not want to be without a working printer. But then..... I decided to try a CoreXZ arrangement. The idea has been to make it easy to re-build into a double NEMA14/M5 Z axis Huxley, if the experiment proved to be a bad idea. Running Marlin RC7 with mods, it has done its first print today. I have had a bit of a time working out heat settings and feedrates with Marlin, but others on the forum have shared information that has either answered my questions or triggered some thoughts in a new direction.