The Guide build step creates the guide nodes for components.
If you change component settings, rebuild the guide to reflect the changes in the scene.
At the bottom of the Build tab, choose Selected Components or All Components to choose which guide components you like to build.
Side building is used to create a side component out of an existing component, essentially mirroring guides.
Inactive: Builds the sides according to the component settings.
Right: If a left-side component is selected, a mirrored right-side component will be built. Choose Selected Components at the bottom of the Build tab. If you choose All Components, the right side mirrored from all left-side components will be built.
Left: According to Right.
The face components ignore side building. They always build the left side for the guide and both sides for the rig.
If you wish to import guides from an external asset or the same asset (essentially duplicating components), activate From Asset in the lower section of the Build tab. This allows importing guides using the Guide Picker that will show up once you click Build.
Loading guides requires a guide file to be saved under File -> Save Guide.