It's an old note the devs would leave for the designer (me). It shows up everytime the site can't render a page. The powers page was fixed earlier and maxwell is working on a more creative version of the 500 error :)
Characters get rolled up to the franchise from the actual episodes and manga they appear in. For example, if you want to add Spike to Cowboy Bebop, you'd want to go through every cowboy bebop episode and add him there. That way the franchise will go... hey, I see that Spike was in 13 episodes, he must be important!
Images must be 100x100 pixels or larger. While I can see users wanting small images for their icons, we do it mostly as a protective measure to prevent people from putting crappy images in the wiki galleries. Sorry, we should probably put some better alerts in there.