I love this site btw. I have noticed one area that could greatly improve the mapper though. That is, adding a "Save As.." function.
1. This will improve mapmaking efficiency. If this feature were implemented, we as DMs could write up a map, Save As..."DM's Map", then refer to it as things get revealed. Being able to save a copy of a map as another name (thereby making it uneditable by players, and unaffected by the latter changes I make) is a highly desired feature on my list.
2. Players aren't perfect. Someone could try to move illegally. It seems that being able to have a DM copy prior to player turns will help immensely in the event of human error or pure mischief. In a system with open access for all players to save over my old map, it almost seems a necessity to have implemented Save As functionality.
3. Map reusability. As of right now, we can create a map full of grass and random rocks, but cannot save the map for later use to add on to it later. If I could, I might could save the base map as "Field1", and then make one with flowers all over it and call it "Field of Dreams", and then load up the Field1 map again, and add fire or rocks all over it and call it "Field of Ruin". I could then reuse the basic Field1 template to create a variety of similar but also different maps in a matter of minutes. This would be especially handy for when the next 10 encounters are all in the same dungeon, or temple (I could keep the motif as well without having to redraw it).
Possible design concern: db space.
I am sure that since the mapper is light you aim to keep it that way. If server space is the reason for not having such functions, then I would request Load/Save As functions instead (in fact might be better all around for you..). Allowing DMs to save the datafiles to our local hard drives instead of always to the server would certainly take the load off your server for all but the 'current map' for each campaign.
