I´m closed starting the build of the BLV Core XY in combination with a tool changing system designed by "smoki3": https://www.thingiverse.com/thing:2946805.
This guy is using the DUET board as well, so it should not be a big deal to combine both Things at the end. The x carriage will have to be modified for Ben´s belt alignment.
I have started buying and printing the parts required for the CoreXY and the tool changer system. So, nothing to show right now.
Hope to get into the build itself soon, but time is limited as well.