Coaltion does work a bit different than most Wordpress themes if you are using the one page setting. You can change that if you'd like in the main Coalition Theme Options. Its the first dropdown under the Insert Dummy Data button.
Using the One Page Portfolio option, all of the content is loaded into the single home page by the One Page Portfolio template. If you loaded up the dummy data, you'll have a pre-built template here you can edit.
3) To display text excerpts with your Portfolio, you just scroll down to the Portfolio element in the template builder for the One Page Portfolio and expand it so you can see the options. Then select Yes for the Portfolio Excerpt.
4) Using the one page portfolio option will also mean that the Cufon plugin will most likely not work well if at all. The content is handled by the dynamic template and so wont be recognized by the plugin.
1) I'm not sure they can be re-ordered other than by alphabetically. I'll check with Kriesi to see if this is possible.
2) The portfolio display unfortunately can't be randomized. They will show up by date, starting with the most recent first.