Any way to speed up round corner processing time?

Hi all,

my second question of the day.
I tried to apply fredo round corner tool to the boulder, but it seems it takes too much time.
I do know it can be shortened by reducing the offset, but it still takes way longer time than the tutorial shown in the landscaping exercise in Sketchup. I don’t think it is caused by my laptop because other processes are running smoothly.

Besides, I also notice for some of the line I draw, some overlaps are created which affect the round corner result, is there any method to remove the overlaps (extra line)? Rather than redraw the lines?
Thanks a lot!

sketch up May2 round corner
Landscape exercise.skp (11.6 MB)

There are better ways to create stones/boulders. You can start from a low-poly sphere (better icosphere) and modifying it with Scale (better Vertex Tools).

Search YouTube for tutorials.