Indeed…it’s been a persistent issue!
Since my façade is also parametric, it’s very hard to keep track of indices.
I’ve also tried that plug-in but without success (the corner is “filled in”):
An alternative way of going about it, that I am also exploring at the moment, would be to draw a polyline passing through all the points at a given height, then loft them to form a “meshable” surface…yet I’m stuck because for some reason points are omitted during the sorting process.
Link to that problem…if it helps!
(How to separate and order points by z & x coordinate (for connecting by polylines + lofting)?)