I didn't make it!
NO DEV MODE WORKS ANYMORE TO START CUSTOM MAPS. NOW YOU NEED AN APPLICATION CALLED COH LAUNCHER. GET IT! IT WORKS FINE! cAN BE FOUND ON COH Launcher - Planet Company of Heroes
.... Or you CAN use -dev mode....or just use a decent map that has been compiled into sga format...that doesn't require -dev... Why download an app you don't need?
There are parts of the .sga maps that don't work anymore, like the minimap in the skermish menu and the weather options, you would have to extract these things and then run it in dev mod to get them working. the launcher fixes those problems and lets .sga maps work online. Also for some people the launcher is probably easier to use than -dev mode.
~_^ Serious? I havn't had an issue with sga maps yet lol... Ohwell, I guess it'd be easier then using the dev mode