CIP from ema-eda tool to Cadence

I would say "sometime around" July 2015. As I understand it, the "original" EMA offering was for "bundles" of 10, or more, user licenses, and therefore, primarily intended for multi-user environments, for "about" the cost of 10 individual licenses, although there was an option of singular licenses. It turned out that singular licenses were a lot more popular because folks could purchase "exactly" the required number of user licenses, regardless of packaging offers, and this is the model that Cadence has adopted for their offering of the CIP product. So, if you purchased an "original" EMA package, it could be very likely that you would have purchased a license for 10, or more, simultaneous users, these user licenses could be converted to the same number of user licenses for the Cadence CIP offering when the maintenance was renewed. Strictly speaking, "a" license could support "any" number of users since the "simultaneous user count" is part of the license encryption, but a single user license for the EMA CIP product would allow access to just one user, the same as a single user license for the Cadence CIP product would.

At work, have 8 DE CIS tokens but four floating tokens for CIP.

CIP sessions are shared by anyone having a CIP login, provided there's a session available.  Check your license server status for the availability of the CIP option.  

You might have a system issue.  I have not found any nodelocked licenses in the Cadence catalog (OrcadMarketplace plugins are handled differently.)  

If Windows Authorization doesn't work, ActiveDirectory might have an issue.  Try the Admin account or a non-ActiveDirectory login on CIP.