Current questions and answers regarding the map editor.

DDS, you are right, as Ment said.
By default, Photoshop cannot save in this format.
Therefore, for DDS, if you are using Photoshop, you need a special plugin (Google will help you find the plugin, because I don't remember the link).

Added 8 minutes later
Using scripts.
We attach a trigger to the building. (An event occurs when entering it)
In the trigger execution function, we write the code to receive gold for sulfur.
(if GetPlayerRe.... == 20 then SetPlayerR....(GetPlayerRes...(Player_id,(gold)+1000))
If it's not clear, then study the script alphabet ;)
You can learn it in the manuals, on this and many forums, using the internal search, and if you need specific details, then you just have to wait for our forum's "Archivist" ;)