Good questions, but a little too complicated to cover in a general answer on a public board Retain a lawyer to get a confidential opinion.

Is it directed towards a child under the age of 13?

You are focusing on just one fact. Let's assume you are talking about the settlement between the FTC and Youtube and the consent judgment relating...

While you say "our legal team" you don't say what type of entity "we" is. Don't mention specific names, but a company could be different from a...

Assuming by "replica" you mean "counterfeit", only if you want to get sued. Is it worth $1000 to $200000 in statutory damages?

Can you Patent a better researched alarm sound and/or pattern for Co2 detectors?

It seems to be the right subject matter for patent -- it's connected to technology not just an abstract idea. Any patent needs to be new, useful...

What is the statute of limitation on a manufacture faulty product?

The most likely analysis would be based on contract. A warranty is a contract, or selling a defective product is a breach of contract. You sound...

It depends on the goods. Trademark rights are national so if you sell with a mark similar to a distinctive mark and sell the same goods there is...

How will I know if I were in trouble?

Stick to only "making graphic designs" that are original. If what you're suggesting is trying to sell unauthorized versions of someone else's...

Can I use a third-party name as part of my commercial software?

The answer above is a good one, but the facts are less clear to me. If the mention of the names is only to identify them as an object of the app...

It doesn't sound random, it sounds like it is a website selected specifically because it sells tee shirts. If they have graphics (art) authorized...