I only ran into this problem once so far on the humaworm. I fixed it easily enough though by taking one 00 capsule of epson salt. It's not enough to give you the runs, but enough to get a little movement going.
I had been sick for so long that I hadn't had a solid movement in about 6 weeks, which was part of what led me here. Since starting the humaworm, I've had my first normal movements in ages pretty much on a daily basis except in the beginning. I never thought I would look into the toliet and use the word beautiful on something I produced, lol, but seeing the proof that my system is well on it's way to recovering sure seems beautiful to me!