From: Bexhill-on-Sea, E Sussex
I've played Shadows about a thousand hours as a beta tester since Jan, and even I don't know the answers to those questions, don't use the resource planner much anymore except to check for good colony locations. I use the galaxy map filtering by resource mostly myself for constructors, and learn the territory near a spaceport for my state mining ships. Maybe Elliot or the staff will answer your questions, or better yet put the answers into the Galactopedia, which is sadly outdated.
Lonnie Courtney Clay
Personnally the more I play the game the more I'm beginning to agree with you, although it's not completely useless it is pretty close to being so, with many of the terms missleading.
Finding Potential Colonies is what I use it for most but even that has it's flaws. For instance, distance! Distance from what? To be useful you should be able to set a starting point but if, as I suspect it's the home planet then why? Not all colony Ships are built on the home world.
Resource Targets by your Your Empire does not include all resources you are short off. I've forgotten what the actual problem was here but I posted earlier when it first came up. I now use the Galaxy Map filter like you.
The Galactopedia (and manual) lack vital information for playing the game. Another for instance, you do not know what resources are needed to build ship components prior to researching them. I use this knowledge by, in theory using the Expansion Planner to located the needed known resources, send Constructors out to mine them. This would enable me to be as ready as I can be to once the component is researched.
This is called planning.