Choose a tool from the toolbar and paint into the map.
Hold Shift or Control down + click for erase
I recomend to use Google chrome for use this editor. It's javascript intensive and needs a good performance browser.
The editor does not work in IE7. And i'll not fix it
JNKPlat By: Jayenkay, jayenkai [at] gmail [dot] com
Online Editor By: Adael, adaelxp [at] gmail [dot] com ummmm... yes, it's in javascript
www.adael.es - My personal page. In spanish