How exactly did you try to do this? You should have been able to travel back and forth between the two worlds if they were in the same ongoing game and not be presented with a brand new copy of either one if the mod's Change Hometown had been fully invoked on the first household.
You also could have stayed in the second world and used MasterController to pull the next household in and place them in a residence without leaving. They lose their wealth and possessions this way, so some players do the back and forth thing instead to move them in but sometimes the quick way works out better in the long-run.
http://www.nraas.net/community/Traveler-FAQ
(See the Switch Homeworld section and the part about pulling sims in to a new world towards the end)
