Suggestion.
Create a new topic, titled along the lines of "RPG Reference information". Those behind the storyline make the first few posts, outlining the details of setting. Who the characters are (Vacuum EVATs from a specific Earth Marines Squadron, correct?), what equipment is available (Kinlas, machine guns, EVAT suit capabilities, Pharris generated this well), and the basic premises upon which characters should be made. In this case, I believe it is a functional squad member of an EVAT squad, or someone who will very shortly become part of said squad.
Then, everyone outlines their character in a way which fits in with all this, with minimum bending of capabilities, technologies, and plotlines. That might spur a few inter-character relations ideas (Tim met Joe on Planet X, and they've been arms buddies ever since). That kind of detail can be worked out in between players over email and in separate topics to add depth to interaction between the characters.
Finally, once the characters are established, and rooted firmly as members of the squad and universe, a fully immersive RPG will proceed naturally. I imagine that this would take no more than two to three days, assuming minimum fuss over limitations, and will result in a much richer and more rewarding story.
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Sundered Angel ,
The One and Only
Ares Webboard Moderator, and all-around Nice Guy