Well done for taking the time to put that together. I wouldn't have the patience. There was no instructional sound with it, I assume, or is it my laptop playing up?.
I use essentially the same technique but don't have Photoshop (I use an old version of CorelDraw) so don't have quite the immediate gratification going from the overlayed uvw to the garment laid on the Achat model (I have to go via something like Irfanview due to the way transparency is handled). It also means that texturising isn't quite so easy too.
Of course, life would be even simpler if we could wrap on the appropriate 3D model directly, in whatever product we use.
Prias I don't understand how anyone can work with other than the uvw as a base. You're restricting yourself to a garment based on a garment, as opposed to using the full capability. More power to you.
I have looked at other products and Photoshop seems the best but there is no way that I will pay such a horrendous price for the return of a few $A