Hi Pilou, well the tricky part about these things is that many operations are approximations where there is a mechanism that repeatedly refines a result until it is accurate enough.

If the accuracy level is set to be too high, then it can produce really dense results, like with many control points in it.

It turns out that the surface offsetter in the geometry library would stop trying to build the offset when it hit a certain number of points. That was causing many of these offset problems. But I've been able to change that so that it will not be so sensitive in the next beta.

- Michael