First: Welcome to the forum although I'm rather late
And congratulation to your nicely crafted sling.
Could you post the drawing of the sling on the photo? Could you also outline the "verbal proof"? I'm always interested in new designs. In this piece especially the transition into and from retention and release cord seems to be quite difficult to get right.
I've seen a very similar design in a depiction of a sling from Rarotonga, Cook Islands.
Here is the link:
http://nzetc.victoria.ac.nz/tm/scholarly/BucArts-fig-BucArts301a.htmlMe and Pikaru made two quick reconstructions/proof-of-principle pieces:
http://slinging.org/forum/YaBB.pl?num=1172017416/3865http://slinging.org/forum/YaBB.pl?num=1172017416/3775regarding slings from the pacific you may also find some interesting information in Pikarus blog:
http://itanohu.blogspot.ch He is also using pandanus and, if I remember correcty, has also tried hibiscus and coconut, although with mixed results. Unfortunately he seems to be inactive at the moment.