I never tried to make an isometric game, so i might be a little far from the best way to do this... but my approach would be:
- Place the action point on the center of the isometric base. Something like this (X marks the spot... or action point
):
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- To make sure that all my actives are with correct positioning, i would also create a photoshop template (or use other software that uses layers) for each kind of cell positioning.
This way i can position the sprite easily on the center and when exporting to png i would just hide the guidelines.
Check the attachment for a PSD template.
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- Finally import the png on CF and center the action point (do not use the center of mass). To avoid extra blank space, you can just click on the crop image.
I created a modified version of your mfa so you can check it out.
On this example i never cropped the images so you can understand a little better how i exported the png. You can crop them later on CF.
I also created an option to create objects on the fly... just click on your keyboard from 1 to 4, then click on the left mouse button to drop an object.
All objects are snaped to a 8x8 grid.
If you see some weird overlapping, it's because the objects were created with a wrong placement... i'm assuming that overlapping cells will not be allowed in your game.
If you are not using some sort of snapping to avoid overlapping, i think that you can't prevent those problems because the actives are not real 3d.
Hope this can help you out.
Like i said before, this would be my first approach... i don't know what other issues i would encounter later so don't take my word for granted that this is the best method available.
Maybe someone with more experience can give better advice 