Yeah I had an idea like that too, something where users could make there own maps. Take a look at the wiki here: [url:3goy3wxu]http://apps.sourceforge.net/mediawiki/construct/index.php?title=Image_List_Object[/url:3goy3wxu] Then some information on ini: [url:3goy3wxu]http://apps.sourceforge.net/mediawiki/construct/index.php?title=INI_Object[/url:3goy3wxu] But it suggests using Array instead. I guess starting out it would be for each object (ordered) get x,y coords
Well its more or less for our own use not for user created levels... our current project wont lend itself well to a create your own level style play... We also really want to do our best to stay away from the the grid style game...
David made a non-linear level editor that will allow you to place objects wherever you want and whatever angle you want. It's a little cumbersome to create things with, and it only exports a string of numbers but those are things that can be changed. You can always translate that string of numbers into a map file. It should give you an idea at least how to go about making the editor.
If you want to make your maps save into an INI file, you can use my example i made for SuperV [url:2no3jfi4]http://www.scirra.com/phpBB3/viewtopic.php?f=16&t=1721[/url:2no3jfi4] (scroll down to the latest version of loader and editor)
Using INI style grouping and values can make 3rd party editing easier/possible, that way you can just tell people who don't like your editing program to go make their own XD