Hey rcmatz,
wow, a Post up them failures!
Here one can see once again, the software and the machine cannot do it by themselves, you still have to be an engineer who has to look after everything 
Poor little makita! 
CAUTION:
- Since excessive cutting may cause overload of the
motor or difficulty in controlling the tool, the depth of
cut should not be more than 3 mm (1/8") at a pass
when cutting grooves. When you wish to cut grooves
more than 3 mm (1/8") deep, make several passes
with progressively deeper bit settings.– Source. Makita RT0701C Instruction Manual