Drag placing is a really cool feature!
But it needs some polishing.
1) Rotate-while-drag doesn't have any visual cues for current direction.
2) It builds unfunctional mess in some situations. I.e. place two pipes with one tile between them and try to build a belt over them. Belt correctly jumps under them. But if you accidentally move your mouse back it adds more undergrounds that break the flow.
P.S. Ah, I understand. R doesn't set current rotation as usual, it just allows to bend the belt to either side. Works good if you move the mouse and then press R. But still looks slightly unintuitive when you press R and then move the mouse.
Edit: screenshot for the second issue.
[kovarex] [1.1.9] Drag placing belts does not tunnel obstacle with one tile gap correctly
Re: [kovarex] [1.1.9] Drag placing belts does not tunnel obstacle with one tile gap correctly
Thanks for the report, the smart belt dragging will now register existing underground belts and only build ending pieces when the existing underground belt isn't already conneted to ending piece.