As of late last night, you can now download (no SVN required) a tarball of a fully-operational Solar system with the 1.0.0alpha2 code in place.

http://svn.solarphp.com/system/download/solar-system-1.0.0alpha2.tgz

1. Extract the tarball directly in your document root.

2. Make the "tmp" and "sqlite" directories writable by the web server process; e.g., chmod -R 777 tmp/ sqlite/.

3. Browse to the "hello" and "bookmarks" apps to watch it work.

After that you can start changing configs, adding your own libraries, and building your own applications.

For a bit more info, see the Download page.