Random coordinate shift for short. (Happens at random?)
When moving a base piece, other coordinates that shouldn't change such as the y and z coordinates change very slightly, misaligning the parts.
This makes building long roads at angles annoying as the edges get misaligned (photo 3)
In relation to the photos, the first is a newly added road part, unmoved relative to another road part. In the second photo the road part was moved in the x axis, at an angle of 1 degree the y should change but the z shouldn't.
@HelixX how is a difference smaller than a milimiter visible? This issue is sadly hard to solve without including a rounder