Thx guys, I've updated the link in the first post, the mirror creator is a bit of a pain.
I'm just finishing the tutorial to make flag animation sequences in After Effects, you can also use Photoshop, I made actions to import and export the sequence's, but AE is much easier and quicker.
I'll post instructions for using Photoshop later as some may have preference to that software.
This is the method i use to create all the animations in GP4, all you need is 10 frames of animation and combine them into one atx sequence in After Effects.
I use 3ds Max for UV Mapping, so I don't have a clue how you would go about mapping these in GP4builder, maybe someone else could write a tutorial for that.
F1Dev