When a station needs to display rumors you can use a call to msfShowRumor (or put the companion function msfGenerateRumor inside a "noMissions" Text tag so it gets called by rpgMissionAssignment when there are no missions available)
The rumor framework then builds up a list of suitable rumors by calling GetRumors on all active stations and all missions (both active and completed - so major missions can create rumors in multiple systems), GetGlobalRumors is called on all types. The returned rumors have three parts:
- Text to display
- A priority (higher priority rumors are more likely to be displayed)
- Optional code which will be run if the rumor is shown (can be used to reveal stations as done by the pub rumors)
EDIT - the latest version can be found on github: here