Incredibly usefull plugin.
I've found a very annoying bug on the new version on Sketchup 8 Pro though. It used to work great with the previous versions.
It fails to create a new layer and move the group backwards a bit so it appears on the section view. I've tried several combinations of the plugin's preferences and all resulted in the same bug.
Here's what i got on my ruby console window:
Error; #<TypeError; reference to deleted Edge>
C;/PROGRA~2/Google/GOOGLE~3/Plugins/SectionCutFace.rb;361;in `faces'
C;/PROGRA~2/Google/GOOGLE~3/Plugins/SectionCutFace.rb;361;in `initialize'
C;/PROGRA~2/Google/GOOGLE~3/Plugins/SectionCutFace.rb;359;in `each'
C;/PROGRA~2/Google/GOOGLE~3/Plugins/SectionCutFace.rb;359;in `initialize'
C;/PROGRA~2/Google/GOOGLE~3/Plugins/SectionCutFace.rb;358;in `times'
C;/PROGRA~2/Google/GOOGLE~3/Plugins/SectionCutFace.rb;358;in `initialize'
C;/PROGRA~2/Google/GOOGLE~3/Plugins/SectionCutFace.rb;476;in `new'
C;/PROGRA~2/Google/GOOGLE~3/Plugins/SectionCutFace.rb;476
C;/PROGRA~2/Google/GOOGLE~3/Plugins/SectionCutFace.rb;361;in `call'
C;/PROGRA~2/Google/GOOGLE~3/Plugins/SectionCutFace.rb;361