Two things have changed.  The file format changed, first of all, so older maps may no longer be recognized.  Secondly, the directory has also changed. 

To solve the first problem, you'll need to find the file converter that updates old map files.  I'm not sure where it is; try a search in the modding forum.

As to where you should put the files, the new directory is C:\users\<username>\AppData\Local\Ironclad Games\Sins of a Solar Empire\Galaxyforge

Hope that helps.

Oh right, the directory is named differently in XP:

C:\Documents and Settings\<username>\Local Settings\Application Data\Ironclad Games\Sins of a Solar Empire\GalaxyForge

I also forgot that you need to reveal hidden folders (control panel -> folder options). 

And yes, the current version of GalaxyForge saves maps in the correct format.

My avatar has been uploaded and isn't showing yet. (yes I refreshed) Does it pend approval?

The folder you need to find in contained in the same folder as the mod folders if you know where those are. If not, open the options from the main menu, go to the mods tab, and hit the find mod path button. The folder right above the mod folder is what you want to find (where ever it is, note that you have to go through a hidden folder to get there). Then find the folder that says GalaxyForge and paste your maps in there. They should then appear in the GalaxyForge section of the map selection menu.