ID:163612
 
I don't know where to put this, but I'll get to the point.

When I put transparent icons on the map, they just look solid. Is that supposed to happen, and how can I fix that?

(Version 400.951 obviously.)
What do you mean transparent like invisable things? you can make there layer=0 and then if it does something(such as spawning) change the new spawned item to a higher layer
This is a known issue. It occurs because the map editor doesn't use OpenGL rendering, so it doesn't display alpha transparency.
The map editor doesn't support alpha transparency. You'll just have to work around it.