Issue with tilemap and painting

Hi guys, I do not know what I am doing wrong but I simply can not get the paint to work from the tilemap. I am attempting to do the creator kit: RPG and I've hit a wall before I really got started. I select the tile i want but when i click on the scene it simply does not do anything.
I click on background under tilemaps, make sure that the active tilemap is set to background, then select the tile I want and click on a tile in the scene, but nothing happens. Is there something obvious I am missing? thanks in advance!

 

I ran into this too, make sure you are actually clicking in the Scene and not the Game tab.The way the panels default puts the game and scene tabs right next to each other. I pulled mine down and docked it next to the project tab. Hope this helps!

 

Thank you Hyrule, This is exactly what I was doing.