They're warm up exercises, not the main focus of the course.
Of Ex. 10-15 using all finger combinations, Ex 12 with the 1st finger and pinky is the one I really suck at.
It's something to work on, but not something to dwell on til you perfect it.
I still can't do the first warm up, Ex 3.
If I'd waited til I could I'd of never gotten to the rest of the course.
I'm currently working all the exercises in all the boxes at 90 BPM.
I haven't done the warm up exercises in years.
If you're up to Ex 12, there's only 3 more combinations to go and you're done.
Might be time to skip some (or all) of the warm up and move on to the main course.