After importing XML demo content, you are left to organize your widgets as unfortunately wordpress importer doesn't support them.
To build your homepage demo-like, please check the default documentation > Creating the homepage
If you wish to import widgets also, I attach a
.wie file from the Widget Importer & Exporter plugin, which you can use to import some demo widgets from the live demo by installing the plugin and importing the file.
You can download it here
Note: if widgets aren't appearing on the front-end right after importing, please move to Appearance > Widgets and hit the "Save" button once for each widget.
Note 2: Please ignore any widget failing to import, as the live demo has many sidebars for all the homepages layouts, which are not needed to the end user.