Splitting the work longitudinally using the "Along Axis" settings and using a "Base Point" value which falls within the selected section of the workpiece will generally avoid the "Missed Stock" issue which would occurr without setting the "Base Point" correctly, this will result in good paths for most parts.

If you ever have the misfortune to wish to use 4-Axis Rotary finishing on a job that has components which are not round, are well away from the rotary axis and are thin enough that the paths would pass very close to the "Base Point" (even when it is definitely set within the work) you may still you experience problems with distorted paths.

After 3-Axis Indexed Roughing a workaround for this which may help with some awkward parts is to address the section where it is impossible to generate good paths by using two 4-Axis Rotary Features, one for instance with "Angle Start" set to 90 and "Angle Finish" set to 270 and the other with "Angle Start" set to 270 and "Angle Finish" set to 90.

Set your "Base Point" anywhere over on the opposite side from the one you're machining, 10mm beyond the closest surface of the workpiece seems to work. If you were machining all around the job you'd get "Missed Stock" but as you're dealing with it 180 degrees at a time that's not an issue.

Many thanks to BurrMan and Al for excellent tips and tutorials for 4-Axis Standard Rotary Paths, without their assistance I doubt I'd be anywhere near a useable workaround,
Regards,
Nick