I'm also about your build, maybe 5'8 and about 140. It's only been a month since you have had your VFF's, so you are still very early on in transitioning into minimalist/barefoot running. During your transition time it's pretty normal to be frustrated at how slow you are progressing or at any setbacks along the way. Best advice is to stick with it, and relax!
From what you are describing it sounds like you are definitely landing harder on your right foot, and that may be causing a slight wrenching movement. Where on your feet is that blister?
From my personal experience, my first run in VFF's was surreal in how much different it felt than in trainers. It took about 2 months to build up to doing 5k, and I gave myself two bouts of tendonitis in the process. It took a while to get back up to running 5k without injuring myself. At that point, I didn't focus on speed. I focussed on keeping my form together, and staying smooth and light. When coming back from an injury I made sure my form felt good on every footfall until it became muscle memory. I didn't follow a plan or program, I just ran a little further each session. If it didn't feel right, I would either dial back on the distance or take the day off. Unfortunately it was winter, so I didn't have the option of running barefoot. All of my running was done on the indoor track.
Since you were just starting off barefoot and took some time away, maybe coming back running that much was taking it a little too far. The best way to start running barefoot is listen to your skin. When it starts to get even slightly uncomfortable, throw your shoes back on and finish your run off. I think maybe by cutting yourself off before you get to that uncomfortable point in your run, and doing that distance a number of times before increasing may be a great benefit to your form. Transitioning into VFF's/barefoot running is usually a long drawn out process, but if you really relax and take your time you will learn to love running. If you rush, you'll be hating yourself. Let your feet heal, and focus on taking short, light steps on both feet.
It's been since January for me, and I'm now up to running 12-14k comfortably. I just run in my comfort zone, as I've never been an overly fast runner. I've had setbacks along the way, but I've taken my time coming back from each one, and I do thoroughly enjoy plodding along the local trails. Once you are able to run a half marathon or so, adding distance becomes easier, as your body is then able to cope with the stresses of doing the long distances.
As for Barefoot Ted, he is big on 'running by feel'. Going by that, it likely took him at least a year or more to be able to run a marathon. He's got a thread on his site here:
http://groups.google.com/group/huaraches/browse_thread/thread/6450590475d5db99?hl=en#You can even shoot him a line if you would like some more expert advice. Hope my rambling reply helps!
