Bob Warfield just published an interesting article on plunge roughing, where material is removed by plunging a tool into the work in series of overlapping holes. This is very similar to chain drilling, and has some advantages. First, MRR is typically higher than with almost any other type of milling. Second, there is no need to worry about tool flexing/breaking since there's no side forces on the tool. Finally, the Z axis is typically more rigid than other axes, so lightweight machines can use the technique advantageously.
https://www.cnccookbook.com/toolpath-secret-weapon-complete-guide-to-plunge-milling-roughing/To use this for a profile in CB, it's necessary to have a polyline offset from the target polyline by the tool radius plus roughing clearance. I can generate this line in my CAD program, but whether there is a script in CB for this I don't know. Once you have the line, the plunge points can be generated as a point list via the "Draw>Point List>Step Around Geometry" operation in CB. One chooses the step distance according to the tool diameter.
For roughing a pocket, one uses the "Draw>Point List>Fill Geometry" operation, but again you need an inside polyline offset by the clearance. However, in this case you might choose to explode the point list into individual points and delete those that are too close to the pocket edge.
Finally, code a drill operation on all of the points for either the profile or pocket.
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