If they are using the name, even without a registration, they have superior rights. Yes you could have issues and no your old computer will not help

If there is ambiguity in a contract, you need to sit down with an attorney with the entire contract and all written materials.

Can similar names be used under same trademark class?

A very good question. It is possible, not always easy, to register the same mark in the same class. But, there must be enough difference in the...

What can I do beyond sending a cease and desist? What are my rights? What are her rights, if I can even find her?

It would appear as if the other company abandoned the mark and is no longer using. If this is correct, then you should be ok.

Is it legal to use "fan art" of a public figure (being authorized by author) AND the name of that public figure in my mobil app?

You have two issues and have only addressed one of them. The creator is giving you permission. But, you also need permission from the subject.

Would a publicly displayed structure built in 1949 still have copyright protection if it was never registered?

Not a clear answer. If the work was published without a valid copyright notice, it might be in the public domain. If the work was published...

If I have permission from a company to use their intellectual property, can I have ads on my site and podcast?

Are you Sonic Realms? Basically, do you have permission?

Do you play the online game based manga like one piece?

Do you have a legal question about the game?

How can I stop someone to use the videos I have created?

You need to bring all written contracts and correspondence to an attorney. If you were hired to create, then you might not have rights. It will...

We got email for using copyright image and took image down immediately. Still getting emails from them for money.What to do?

Taking down the image does not absolve you from infringement. There are ways to address this and should be done with counsel. BE CAREFUL. Saying...