You can contribute your own maps to the library if you like. The RSW client provides a module for designing maps and submitting them to the server. As a general rule of thumb, you should design maps that have:
To generate a map, select "New RSW map" from the "File" menu of the RSW game list window, within the client. This opens up a blank gray window within which you may start drawing your map. The controls are similar to the map-editing controls within the game, with a few additions. In particular, you should use:
Declaring homeworlds is optional. If you mark no worlds as homeworlds, then the RSW server will automatically select homeworlds for the players in the game that are approximately evenly spaced across your map. If you mark at least one homeworld, then you must mark all the possible homeworlds; and in this case, the RSW server will only select from the marked worlds. Marking homeworlds may limit the number of players that can use your map, since a map cannot be used in a game with more players than the map has homeworlds.
"Passage" worlds are worlds that are critical to keep clear passage, e.g. small bottlenecks between large sections. The server will never place a black hole or a homeworld at a passage world. Most maps do not require marking passage worlds explicitly (the server will never place a black hole where it will completely separate off a section of the galaxy anyway).
Treasure worlds are a further optional feature. Some specialty maps may declare one or more "treasure worlds", worlds that are out of the way or hard to get to, but provide some in-game reward for players who discover them, such as extra industry or artifacts. You can declare Gold, Silver, or Bronze treasure worlds; the precise meanings of these treasures for a particular game can be specified in the custom game settings. Most maps do not use treasure worlds.
When you are done designing a map, you should give it a title, and a set of tags. Tags are individual words that are used to select the map into a game. Each game is set to use a particular "map set", and a map set is a set of words--it means all of the maps that share all of the tags named by the map set.
The following tags are standard:
You may add your own tags in addition to these. Tags should be entered in English. In general, you should add at least one custom tag to each family of similar maps, if you create multiple maps in different sizes--this allows you to select the entire family into a single map set. Also, you should consider adding your own name as a tag to all of the maps you design, so that someone can select all of your maps as a map set if they wish.