i made some notes
1.
extrude along multiple paths. + option closed holes.
usage at train tracks switches.
2.
units, me most working in cm or meters.
3.
a check mark instead of color in checkbox control.
4.
position window near by mouse cursor.
5.
circle with degree input.
6.
insert vertex tooltip, select min. 2 points.
7.
mirror just the vertex points, example x=-x
(found plugin Coordinate Swap for AC3D)
8.
boolean, need a hint for correct normals.
9.
sweep around 90° arc, the angle should be parallel to circle
so the start and end will rotated correct.
10.
multiple boolean union, a list of objects meld together (batch processing)