What you need:
Zombie apocalypse model pack or Mob Zombie 1\2\3\4\5\6\7 or 8 Model
An entity to have the ragdoll anims
Fragmotion
Step 1. Import the X file into fragmotion of the entity that you want to have ragdoll anims.
Step 2. Click on the animation that says Anim-1 and delete it.
Step 3. Click File -> Merge Animation
Step 4. Browse to the mob zombie model and double click it.
Step 5. Click File -> Export
Step 6. Click match bones and click ok
Step 7. If the original model was for example Specialist.X save it as SpecialistR.X
Step 8. Make a copy of the original entity's FPE file and edit the copy with notepad.
Step 9. in notepad edit the following line:
anim11 = 0,19
to look like this:
anim11 = 3310,3370
Step 10. Save your changes to the FPE File.
Step 11. Try the model out in Test Game.
If there are any bugs then contact me via posting something