I believe there is no entity equivalents to the segments currently, but you can create your own.
It is rather simple.
You already have the textures and meshes. Each Platform is just 1 to 3 meshes.
The Fastest way would be to copy a single FPE file in the entitybank.
Open it with Notepad or FPI Editpad
Now navigate over to your segments folder. locate the segment you want to make entities for. (example C:\Program Files\The Game Creators\FPS Creator\Files\segments\scifi\platforms) chose lets say
Maintenance Gantry TJunction.fps then open that with one of the 2 programs.
In the fps file look for
meshname0 = meshbank\scifi\moonbase\gantries\gantry_2
\floor_tjunc_a.x
Copy the
meshbank\scifi\moonbase\gantries\gantry_2
\floor_tjunc_a.x portion and then go to the fpe file.
in it you need to find
model = itema.x
Select itema.x (or whatever the name is) and paste over it.
For the texture do the same process except look for lines that start with texture0 and textured in the fps and fpe files respectfully.
When done you can then do this.