Google Plus – How to Liberate All Data

The bottom line is, no, there is not.

Unlike Blogger, which has a way to write posts externally, Google+ does not have any such public system, and Google appears to have not wanted to support such a thing to migrate posts at this time.

Make sure you use the Send feedback system to make sure they are aware of your displeasure with this situation and urge them to completely implement the migration feature.

You have a couple of issues mixed in here, so the answer may get what you want, but not quite in the way you want it.

For starters, there is no way to assign what will show up in which column. There is not even a guarantee that you will have one, two, or three columns.

You can see posts, in chronological order, from just one circle if you want. Along the top of the screen will be several of your circles listed, you can click on any of them to see just the posts from that circle. (This shows the default circles - you can get to more of them through the "More" drop down, and you can select the order you want them to appear in.)

This is also how you can hint to Google+ which circles are more important to you than others. After you select a circle, there will be a card titled In this circle. Selecting the Gear icon in that box will let you select if you want posts from the circle in your home stream and, if so, a rough idea of how much you want to see this circle.

This is also where you can turn on notifications for this circle. Turning on the notification through the Bell icon means you will get a "Red box" notice when someone from the circle posts, and you may get email if you have chosen that as well.

How you use these tools is up to you. One strategy might be to set it so only your "Family" circle shows up in your home stream, and you need to look at the other circles explicitly. Another possible strategy is to have your Family circle set to notify you when they post, or just have it set to "More" posts, and the others may be show you "Fewer" posts. Keep in mind these are not absolutes, however, just guidelines to help Google determine which are more important to you.