In previous GalCiv games internal migration was done via colony ships. You can load up pop from a planet then send it to the destination planet and unload the pop there.

I haven't tested it yet for GalCiv4 but figured I'd see if you tried that yet.

I tried the colony ship tactic and couldn't get the passengers to unload at the destination planet. 

The titling of the thread was to encourage folks to look at it and provoke a response. Looks like it worked. 

You have to disband the ship to get the population off of it, or use it to build a Colony or Star Base, which also disbands the ship.

Or you can get one of the survey results from Anomalies that give you a mission to build something on one of your Worlds and in return you get some some population units (normally only 1 or 2) of an Alien Race, such as the Torian Academy, Baratak Grove, Krynn Altar, Manti Birthing pool, etc, on that World.

I tried to design a Passenger ship that had both a Colony Module and a Construction Module, and built it to see if it would work as a Passenger ship.

It failed since the population remained on the ship even after the ship landed on a different World than the one that built it. The only way to get the population off is to disband the ship. I hoped that I could unload one of the two population on board like I could in GC III, but it did not work.

My test of the Passenger ship design that failed was this week (about Jan 11) using version 0.70.