I've been seeing this since 0.15.0, but been too lazy to post it. Figured since you want to go stable this week it's about time. I'm amused nobody else has posted it in the mean time.
Using the pipette on a diagonally-placed rail piece picks the wrong diagonal orientation. Pipetting a northwest/southeast rail piece puts a rail piece in your hand (as expected) but it's facing northwest/southeast, and vice versa. No screenshots or save file since it's so simple to reproduce and 100% reproducible for me.
[0.15.28] Pipette picks wrong orientation for diagonal rails
Re: [0.15.28] Pipette picks wrong orientation for diagonal rails
Thanks for the report.
Fixed for 0.15.29
Fixed for 0.15.29