Well, I just went through this exercise with data from one of our customers... some info was done with Apex setup... and some was done with EASi Suite setup.   I was able to reconcile the differences and "merge" the differently named data.    But I'm not going to tell you that it is an enjoyable exercise.

Here is a quick summary of what I did:

1)  If the field had a boundary, I could click on the field node in the tree. Otherwise, I had to go down to an actual product in one of the operations.   There may be places in between, but I'm not sure.

2)  Click on the Edit tab at the bottom of the screen.    Make sure that it displays data for the field that you have selected.   If the field doesn't have a boundary, I had to go all the way down to the operation product node to make this happen.

3)  Click the Farm link (it will be like an internet blue link, instead of a button) to change the farm to which the field is assigned.   This will display a dialog where you have to do two things... click the checkbox on the left side that is the name of the current farm to which the field is linked, and then on the right side, drop down the combo box and select the farm that you want to move the field into.   Then click Apply. 

You can click the "Client" link to move the farm from one client into another, or the field link to move the operation from one field to another, or the product link to merge the product with another, etc, etc, etc.

I didn't say it was pretty, or fun, but it worked for me.   I could not figure it out, but when on the Edit tab, I pressed F1 to get the online help, and that did a decent job of explaining it.    Had to just experiment to figure out that the Edit tab would not contain info for the selected field unless the field had a boundary.

If you get Stellar Support started in the right direction, they might be able to give you a better set of steps.    I would get my farms all cleaned up first, because maybe some of your fields would "auto-merge" with existing fields when moved into the new farm.

Hope this helps.