There is an ACE Update bounding box, which works during runtime, please try that, it takes a little perf from the C3 engine, so update sparingly if possible (e.g. not every tick). Also, you can adjust zHeight if it's due to the camera looking 'up' above the model.
There is also a new ACE: Set origin x/y which can help 'center' the bbox depending on the 0,0,0 point in your model local coordinates.
In the picture below, is the model the L shaped desk? If you reload the project, does the bbox change to match the L shape? I added a feature to update the bbox on the load of the model in the editor. If you are using an older version of the plug-in also try updating.
I've tried using the update bounding box action, doesn't seem to do anything, the center with x/y action would have to be manually done for every model (everything seems to be off center from the bounding box) and I've reloaded the project multiple times and made sure that it's on the latest update. I even re-exported the model to have it's geometry to the origin, still is off center.
The issue is the origin is not centered with this model when it's rotated, I will look at adding an ACE which creates a centered bbox, shifting the origin and the size at the same time. This may also need to be a property for it to do the same in the editor. Right now I have to do this to center it:
