In a group, right click a player and select "Copy Character Name". This also works by right-clicking on a chat message by the character (whisper, party, etc.).
We depend on Blizzard to give us information about characters. Inactive characters, for example, may be reported by Blizzard as not existing.
Certain dungeons are recommended to optimize point efficiency, for the current weekly affix, based on the character's lowest score.
If you only have time to run a few dungeons and wish to improve your score, these are great ones to target!
Sending too many requests for data refreshes to Blizzard, Raider.IO or other services, either simultaneously or in quick succession, triggers throttling to slow responses down.
Therefore we have measures in place to limit the number of refreshes, which allows more users to share usage to benefit from the site.