[elieseif]

Many many thanks. I finally got it to work.

But for anyone who comes across this thread, here's what I discovered.
The call to the api works in GET mode, but not HTTP POST.
It only works in POST mode if you provide the full url with the query parameters in the url and not only as CURLOPT_POSTFIELDS

Both my version of the code and yours work when the HTTP call is modified accordingly, so there was need to fetch the admin and the security token after logging in. The sequence is api.init ---> api.login2 ---> api.save

This is clearly a bug in the api!