first post of topic and link updated
on topic:
I have found a way to add a layer but it is linked to proper saving with all necessary info.
in my case, with the sample player, mini looper, and so on i do have an issue: i have no metadata to add since these are tools.
Probably something that has to be refined, since these new HSSE layers seem to fail to load (macro) in HS3 but go perfectly in HS6.
We’ll see where we end up with it. 
kind regards,
R.