I am also very interested in making that kind of purse. But failed twice when installing the zip.
I first fixed the zip with glue (same glue I use to glue leather) before sewing it on the leather.
But I am not satisfied by the result. I Am pretty sure there's a special technic. So if someone can help or has a pictured tutorial: that would be great!!
I found this video: but it doesn't clearly show how to fix it nicely on the curved part of the purse.
Thanks for your help!!