I've been struggling with getting parts 2677 and 2678 to work together (and with other monorail parts) in Stud.IO for a couple of days now, and after thinking something might be wrong with them, I eventually discovered something wrong with part 2772c01 (Monorail Track Monoswitch (2772c02 / 2774)) instead. After examining this part closely in PartDesigner, I realized that the anti-studs at the bottom are actually misaligned. It turns out that part 2774 is sitting slightly too high above part 2772c02 in that assembly. This means that any monorail that includes the Monoswitch is bound to be misaligned, even if all connections along the monorail are perfect.
I can produce a corrected 2772c01, but it's probably better if someone else does it who has more experience with .dat files and can ensure that the resulting part would be perfectly aligned.
I can produce a corrected 2772c01, but it's probably better if someone else does it who has more experience with .dat files and can ensure that the resulting part would be perfectly aligned.