I am having an issue where if i set the time to turn on sprinklers as a condition the rule works fine but if i then set days of the week as well it stops working.
I can see that both conditions are true but the sprinklers never turn on.
When you hit Done, it's going to give that command, on2() to Back Lawn. Open the Device page for Back Lawn: does it show that command? If you click on it, does it turn on the sprinklers?
You can get around this bug by making the Days of Week into a Restriction instead of a Condition. That's actually a better way to do it anyway. Then your rule would only have the single condition of Time of Day, that you know to work. The Restriction would only let it run on Monday and Friday.