1.) UI
What are the parameters for Piano MIC placement ?
- the Hammer-line
- the String height (from ground)
- center of key action

x=0, center of the key action
y=0, string height
z=0, Hammer-line

Example:
MIC 30cm over strings, 20cm behind Hammer, 40cm left center key-action:
x=-0.40, y=0.30, z=0.20

Usefull are Guidelines

2.) Positioning MICs
Only the marked microphones can be positioned.
Currently, even at maximum zoom, no microphone can be selected and positioned if another microphone crosses its path.