@Akuba
You don't need regex for this. If you have access to a shell you can use something like this
Code:
link="$(wget -qO- "http://www.sourcemod.net/downloads-new.php?branch=dev" | grep linux | cut -d "'" -f 2 | sed -n 2p)"
You can see it being used by calladmin
here. It's not perfect but it works for now.