Store a morph target on your target mesh before you do a project all. That will project the geometry and color information. After everything is transferred, hit switch morph target and then delete the morph target.
It will delete the geo information but it will leave the poly paint information.
Trying to do a Polypaint only "project all" with no luck. I mean I do the storeMT and that would work but it isn't handing the polypaint/color information over at all. I created a UV map on the target mesh as well and can place an image map on it and created a texture 2048x2048 but for some reason when I project all I get the mesh changes (even though I've disabled Zadd/Zsub) but no color information jumps at all.
Ok the main problem is that the mesh I was trying to project from was just showing me the texture map I was previewing on it. I had to create a polypaint from texture so that the texture I was seeing on the mesh is handed over in pixels to the polypaint. This then is applying the texture to the surface of the source mesh and will then in turn allow the project all to hand from the source mesh (polypaint) over to the target mesh (polypaint).