Reign9000
You can use a shared mailbox you just have to add an account that does have a license as a delegate with full read and write access, uncheck the Strict Matching box in the Auth Config popup, and login as the delegate when it brings you to Microsoft.
For #3 (if I understand you correctly) you'd have to create a Filter with the appropriate Rules matching the criteria and Actions to Assign to whatever Agent. If it's different Help Topics for different Agents you'll have to create a Filter for each. You can have two separate Actions on the same Filter to Assign to a Team AND Assign to an Agent but you cannot do multiple of each. Meaning you can Assign to one Team and/or one Agent per Filter.
For #4 we do not have Round Robin Assignments but this is on our Roadmap for post-v2.0 so stay tuned!
Cheers.