Hi,
I've managed to setup W3 Total Cache (which is great caching plugin) for sites running on WP Hive. Maybe someone someday will find it usefull so there's the whole story on my blog: http://tech.barszcz.info/2010/08/30/wp-hive-w3-total-cache/
One important note though: this solution will only work for setups with sites installed on subdomains. I think it'll not work for sites in subdirectories.
I hope it will be helpful for somebody.
