For some reason this plugin twists the hair guides/splines and the resulting mesh just comes out wrong. What's the problem with it? I tried reinstalling it and it's still the same
To fix this problem use the "Orient Based on Strand" option in Ox Mesh From Strand's modifier Billboard Hair Settings rollout. Or you can fix it by moving the guides slightly so that they are not straight. The problem stems from the fact that billboards don't know wihch way to face when the strands are perfectly straight.
Thing is, "Orient Based on Strand" just gives me planes that are rotated in a most undesired way and the problem with twisting persists even after styling/grooming the long hair. No problem with short hair, for some reason.