PROGRESS! Ashley has let me know that my suspicions were correct. Turns out that RotateAngle() is basically the same as C2's "Rotate towards angle" action, which required me to change some things and introduce a new 'angle sensor' purely for the sake of replacing the 'pvAngle' variable so I can take advantage of this.
The result, as you can see in the .capx, isn't perfect, but it's getting there. The angle isn't spazzing out, but there seems to be some odd delay at times, which makes me suspect that there is indeed collision issues.