[XeTeX] Beginner questions

[André Bellaïche]

I am new to XeTeX, and I could not find a text for beginners. 

I have adapted the following preamble from a sample by David Perry:

======================================================
% !TEX TS-program = xelatex
% !TEX encoding = UTF-8

\documentclass[12pt]{article}

\usepackage{fontspec} 
\defaultfontfeatures{Mapping=tex-text,Scale=MatchLowercase} 
\usepackage{xunicode} 
\usepackage{xltxtra} 

\setmainfont{Frutiger® 55 Roman} 
\setsansfont{Frutiger® 55 Roman}
\setmonofont{Frutiger® 55 Roman}

\usepackage{polyglossia}
\setdefaultlanguage{french}
\setotherlanguage[variant=american]{english}
=======================================================

Let me ask some questions: 

1. Is it possible to replace unicode by applemac encoding? What are the commands in this case?

2. If the main roman font is Frutiger® 55 Roman (Linotype Original names), I doubt that the system will find out that if the italic, bold and bold italic counterparts are Frutiger® 56 Italic, Frutiger® 65 Bold, Frutiger® 66 Bold Italic.

The same font is sold by Adobe under the name Frutiger Std™ Roman, and Adobe says that other names of the font are:

Postscript File Name: FrutigerLTStd-Roman
MAC Menu Name: Frutiger LT Std 55 Roman
Windows/PC Menu Name: Frutiger LT Std 55 Roman 

What puzzles me is that in the XeTeX samples I have found so far, the font name used is the Menu name (with spaces), and not the compact Poscript File name.

André