Okay.This is why being able to make entities by hand is so nifty.
You need four things...
1. A small image that represents the entity (this is what you double click on in the library when you use FPSC...it is kind of optional and the entity making programs generally take the pic for you).
2. The model itself (the model has to be animated in the modeling program you make it in if you wish it to be so).
3. The .fpe file.This tells FPSC how to use the entity.Information regarding an entity and how the animations work are included here.To get a better idea open a similar .fpe to the entity you are putting into FPSC and check out how it is done.
4. The texture.
If you have all of these in the same folder or have specified the correct file paths to these in the .fpe file your entity should work.
Just a note...I import all of my animated models into FPSC by hand like this except weapons.
If you are making static entities though stick with one of the great entity making programs available.They are quick and easy to use.
RIP Floating Skull unknown-2007 we will miss you in FPSC x10