ttttt wrote:1 how do I save a map
2 how do I match them up
This requires one of the custom clients such as Enders (found in the Wizards' Tower forum). As far as I know, Ender's client is the only one that will save the cave maps.
Find where you enter your cave at on the maps saved in the client folder. (I think all the custom clients save surface map data as it's loaded anymore.) You can align the cave entrance of your saved cave map with the surface map. Again, see the above post about what software to use to do this with. If you don't really know how to use image editing software, there are plenty of good instructional websites for all the major software.
Opinions expressed in this statement are the authors alone and in no way reflect on the game development values of the actual developers.