I like this map but i've found some spots where the zeds can't path to the player. The first spot is on either of the flower pots next to the castle entrance. As long as you stay back as far as you can, the zeds can only occasionaly make it to you. You are vulnerable to ranged/aoe attacks though. (https://gyazo.com/d86cd8581b0d91408d98fc1e003eb403 spot 1)

The 2nd spot I found seems to be completely protected. If you run along the fence heading left from the bridge, as long as you keep jumping into the fence at some point you'll be teleported on top. The spot towards the end of the moat seems to make you immune to the zed pathing, including ranged and aoe attacks. https://gyazo.com/07e9be3ebcaf7bd3459dcf79dbb57414
https://gyazo.com/51eeead02d8fe3e4275fc39443d7cd41

Just thought you might want to know.