1) Only a very little, in the second instructional book, The Way of the Four Elements. If you want to add magic to your GSF work you can always use the methods from my books The Druid Magic Handbook and The Dolmen Arch, which are wholly compatible with the Golden Section work.
2) Yes, though that's primarily in the third volume, The Way of the Secret Temple. The energy work included in the initiate's version of the Sphere of Protection in the book you've got is preliminary to that.
3) Theosophists were obsessed by the notion that magic was all about evoking spirits. They were quite wrong, and a good close reading of Eliphas Lévi would have taught them that, but they weren't listening. No, the evocation of spirits is not very important in high magic. It's something you can do with the tools of high magic, but there are many other ways to do practical magic with those tools; in terms of the core of high magic, the work of self-transformation, the only spirit you're working with is your own higher self.
Re: The Line of Work for the WotGS
2) Yes, though that's primarily in the third volume, The Way of the Secret Temple. The energy work included in the initiate's version of the Sphere of Protection in the book you've got is preliminary to that.
3) Theosophists were obsessed by the notion that magic was all about evoking spirits. They were quite wrong, and a good close reading of Eliphas Lévi would have taught them that, but they weren't listening. No, the evocation of spirits is not very important in high magic. It's something you can do with the tools of high magic, but there are many other ways to do practical magic with those tools; in terms of the core of high magic, the work of self-transformation, the only spirit you're working with is your own higher self.