Errors for some transform stuff in Unity 6

[CanHazName]

I have no idea what I'm really doing with this, it's the first time I've ever tried adding external things in but I installed it from the gitURL and have a bunch of errors in the JiggleBone script.

Library\PackageCache\com.naelstrof.jigglephysics@072aec5\Scripts\JiggleBone.cs(59,23): error CS1061: 'Transform' does not contain a definition for 'GetLocalPositionAndRotation' and no accessible extension method 'GetLocalPositionAndRotation' accepting a first argument of type 'Transform' could be found (are you missing a using directive or an assembly reference?)

That and a bunch of similar things all related to the transform get and set stuff all over the script. Not sure if I'm missing something I can't find or what's going on, VS isn't throwing errors though and I'm really confused by this.