Hernan S

From what I've seen Houdini MatX and Maya LookDevX (MatX) are the only two places where you can go back and forth without any issues. Everywhere else they do not have full support. Obviously, you have to use as it was mentioned MaterialX subnet and only Matx nodes, not karma ones. The same can be said about Maya and LKDX

Not quite sure why you are using the old RBD solver. Here is another quick version using Bullet which is much better suited for this kind of stuff and is faster.

If you use vanilla MatX and not the Karma side of thing sharing shading networks should work just fine between Houdini and Maya. Basically, almost everything works fine nowadays that Maya USD is more mature. However, you can still run into issues if you use Maya vanilla USD, if you go through the Bifrsot Graph and author there you can pretty much accomplish the same thing as Solaris, and is procedural, so keep both DCCs running procedurally if you need to.