I'd like to add at least two new era's. Is this possible, and if so, how do I do this?
I'm pretty sure it's not possible, but don't quote me on that.
Many have tried, none succeeded. Apparently eras are hard-coded into the game. You can rename how they are displayed on the screen and the beginning/ending dates, but you cannot add new eras or remove existing ones.
If new timelines cannot be added how about making them a race. Like TMP era for Klinon, Federation, etc. Then place only TMP era ships in that race. Not really a timeline but more choices.
Yes, I think the eras are unchangable, however what ganondorg recommended above is a suitable solution and possible.
I made a beta for a new era, but it did not work properly....it seems to be very hard-coded!!!