I am wishing to make an app that targets a specific fan community for a game by Nintendo. I am trying my best to avoid copyright and trademark issues. Here are my questions:
1) Images I am using do resemble their characters, but it is coming from an art community (not Nintendo) that has a CC license on their art and openly allow people to use their art. Is this some form of inheritance that I am legally allowed to use those images resembling those Nintendo characters?
2) I wish to use a title for the icons that name the character. So, there will be text using the character's name alongside that image. Am I allowed to use their names in reference to the image? What if it has the little trademark or copyright symbol next to it?
3) Assuming any or both of the above does violate the use of their content, I am willing to just leave a text box and image attachment option for the user to add information in their posts. The post would most likely encourage the users to put a character's name and some kind of image from the gameplay (typically a screenshot of the game). The app would not use content itself, but would encourage users to upload their own screenshots and tagging a character's name.
These social media posts will be designed to disappear after a short time limit. The posts will also temporarily sit on a database that the app uses in order to share the information.
Lastly, I am hoping to place a banner ad on some pages. If this, with any of the options above will violate something, could I use a donation page safely to support further development?