You may want to call Adobe on this one... this space is provided by Adobe, there are a couple of employees who check in from time to time, but this is mostly a user to user forum
Since CS5.5 is still very new, there may not be anyone who can answer your question
A license agreement always comes with Adobe software... what does yours say?
In the US - Adobe Activation 866-772-3623 Open 24/7
Read your end-user license agreement.
The subscription license does not differ in this regard.
Yes, you can have the software installed and activated on two computers.