You can submit more than one level. I need as many as I can get so that I can release this game soon. :) -Click an object to select it. It will have a yellow outline if selected. -Drag objects to move them. -If black wall, white wall, or eraser selected, use arrow keys to draw wall or platform. -Numbers to switch between size or types when object is selected. -X to delete selected object. -Space to bring back deleted objects. -Green Flag to reset. To save: -Right-click anywhere on level. -Press 'Save image as...'. -Save to folder. -Remix this project. -Delete all of the sprites. -Upload image from file into the 'background' section. -Share the project if you want me to see it and possibly add it to my next portal game. -If you're creating more than one level, you can upload all of the levels to the same remix, just as separate costumes.