I want to start the camera fullscreen and then put another masked image on the camera and when clicked on take the shot and save the image. is this possible or is it just possible to start the standard cameras with controls?

I believe I answered this in another thread; you cannot display any images, masks, etc. on top of the camera screen while it's active - only the resulting photo.

Hey Peach
Thanks for your fantastic community support. Do you have any ideas when this will be possible in Corona?

No worries :)

I am unsure when this might be available, however you can always make a post in Feature Requests to voice your interest in it.