I just posted the new X-Plane AC3D plugin (3.2 beta 1). For the info, please subscribe to the x-plane-scenery yahoo mailing list. I will post links on the scenery website once the plugin has undergone more testing; during early beta I only need a few testers to tell me I broke things.
Please read the README that comes with the download completely!
An important note for anyone using an existing .ac file to make airplanes with panels:
The new plugin gives you direct control over manipulations. But older .ac files don't have the manipulator set on any of the objects. Thus if you export your airplane, your panel texture will work, but the panel will not be clickable.
To fix this, for each object in the hierarchy that has panel texture, select the object, open the X-Plane Object Properties... dialog box, and change the manipulator from "None" to "Panel". (If you don't see this option, make your properties window a bit taller.)
Note that if you don't need your panel to be clickable, setting the manipulator to "none" is slightly faster in X-Plane 930 and a lot faster in X-Plane 922.
Other details: you'll need the Commands.txt and DataRefs.txt file from X-Plane's Resources/plugins folder.
Panel sub-regions are now handled quite a bit differently - please be sure to read the README completely. If you were using the 3.1 plugin with panel regions, you may need to update your .ac file a bit.