Glad to hear you figured it out - and if you're head works like mine you learned a lot. I learn more when I have to figure out why something fails than I do when everything just works out of the box.
As a developer you are (should at least be) aware how important it is to have a good "bug report". So, if we start with the github problem first - what is the error message you get? Have you checked that the two certificates for github.com and api.gi...
Always nice to learn something new, and after a small improvement of the ABAP Mustache render class (https://github.com/sbcgua/abap_mustache/pull/12) I got this:
After the SICF struggle (hint: don't specify user & password in the service definition) I could get to the enjoyable part of creating my first UI5 application. I had not thought I would do that by writing ABAP code!
