A good start for you is to import some characters (better for your start is to use one static entity, to learn how they work in GG)
from the old FPSC, then you must remake the animation to work fine in the GG
with the "Mender" program for the ".x" character file (the "Mender 2.1 Beta 4" it's free).
After that: remake the fpe file for GG compatible, you can import the character with "import entity" in the edit map function,
then use (or request) some of script for it from here:
https://forum.game-guru.com/board/2 
Smile today, tomorrow could be worse
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