"Curve from end of object" will draw a curve that is tangent to the object you are starting from.
If you have a legal with a chord bearing, it may not be a tangent curve. If that's what's happening, you should be able to draw the arc by drawing in the chord using "line by bearing and distance", and then using that to draw your arc.
BTW, where did you find the "Curve from end of object" command? I haven't been able to find that command, and had assumed it was missing from C3D. Are you using 2008?
Sinc