Pleased your liking our system.
What your request is actually going more into the realm of full LaTeX, where it would be easy to add a picture and caption. In theory we could do this, and its certainly something we can setup for commercial clients, but as the system would use a lot more bandwidth and data, then its not something we can really add to the public implementation - which is busy enough as it is.
However, using a matrix you could layout what you need, adding a caption etc, then splice in the image afterwards using photoshop or something similar.
Sorry we can't help more.