I'm using IIS 7.5 on a Windows 8.
I've got a situation where when I go onto my computer's localhost (192.168.2.6) from another computer connected to the same network the URL Rewrite doesn't work, however, when I use localhost on my computer it does.

this behavior is by design. You don't need license for localhost - developers can test for free. If you have up to 3 sites, you can use Free version of Ape which has no functional limitations. Otherwise, you need to purchase Full version.