1. You are correct that each report section can use only one cube, table, or information map as a data source. The way to use multiple data sources is to use a combination of cube/table/map and stored processes as you are doing.
2. You cannot link a specific part of a chart to different reports. This has been requested before. If you open a tech support track, we can add you to the list of customers requesting this feature.
3. You can pass values from one report section to prompts in another report or report section. An example of this feature is here: http://support.sas.com/kb/26/174.html
... View more