I just bought the pro A* and wanted to use the recast mechanism. I’m using the asset store “Underworld: Cave Environment” and the “Demo1” scene from that. I have also added a small number static object that I found were necessary to get the Unity navmesh to span all the gaps properly. Pressing the “Snap to bounds” button clearly misses out massive chunks (that Unity finds with no problem). You can see the problem here:
I’m guessing that this is an easy fix for you and it’s not likely to hold me up as I can manually set the bounds but it would be nice to have it sorted out ready for whatever else I throw at it.