For security reasons, the browser command must not contain whitespace or start with a slash. The purpose of this mechanism is to avoid commands like rm -rf / or /tmp/rootkit.
226.
Recent
227.
You did not provide us with the url to your link page.
228.
That's because the /RPC2 interface was for the old version 0.3 of Browsershots which moved to http://v03.browsershots.org/ for historic reference.