Re: 5K training and CFFB
With 10 weeks you definitely have the time to work on Pose technique, though you'd be cutting it close on going barefoot/VFF's and being in optimal shape.
I do CFFB 5x week with supplemental running. It runs me ragged, but whenever I'm sore/tired I just eat and sleep more and that usually helps. Your plan sounds good though. You may also look at doing straight CrossFit Endurance closer to the race time (3-4 weeks out). Their programming is similar to CFFB, they have an Endurance (running) WOD each day and an "Anaerobic Endurance WOD" each day. Difference in their programming is that they advise only doing the Endurance WOD 2-3x week in addition to your metcon work.
Honestly you can probably do a 5K fine if you've been doing CFFB (or some variation of CF) for a while (more than a month or two) with a minimal amount of extra training. The above advice is if you really want to hit it hard though.