How does the migrant mechanic work, and is it currently broken?

Sorry if this has been answered. (I think I've done enough searching)

MacGyverInSpace -- Please do not start a new thread in our forum-Doing so cluters the forum window and makes searching for information difficult for all forum participants. - this question could have been asked in any number of other EXISTING threads. We appreciate everyone's cooperation on posting in Existing Threads ONLY !

The Migrant is not functioning at the moment - bug reports have been filed and we are working on the problem -- should be operational in patch ViSa v3.1