Hey there... Effective webbed hands/feet are something I wanted in Poser for a very long time and went through more iterations of developing than I care to think about. The end result was actually a derivative of the solution to another problem: smooth deforming wings. For a very long time now we've released figures that had wings that had very smooth deformations, with tons of ERC/Easypose controls. The method we developed for this was simple and effective: the wing was kept as one single group, with a set of "dummy" bones inside that are all direct children of the "wing" in the hierarchy, yet have had thier origin/end points set as though they were actually chained to one another. From there, we setup the ERC/Easypose controls on them, with the dials on the wing part so that they are easily accessible, then spent a LOT of time working out the joint parameters of all those "dummy" bones. This worked out quite well for wings, and when adapted to utilitze the proper names and rotations for the fingers/toes, turned into the basis for the webbed rigging on the Phibian's hands and feet. This method is kind of a pain, but the results are worth it. It's actually far easier on a wing because that type of bodypart is much more forgiving than fingers with webbing where you expect the finger to appear rigid and the webbing to seem stretchy. The most important aspect of getting working webbing in the fingers is to make sure that the joint parameters are dead on and that you have really stroked those spherical falloff zones to the absolute best they can be. Rigs like this are, IMO, probably some of the most unforgiving developments that I've ran across in Poser yet and they take a ton of patience and practice to get through.