Zombie Survival Test

Basically this map is a zombie survival map. Its not to long of an adventure but its more than just a few obstacles. Its my first map so contact me is you see anything wrong with it or wish to give me advice or new ideas for future maps! Thank you!
**UPDATED**
try this new map I made! https://web.archive.org/web/2020/http://www.minecraftworldmap.com/worlds/h1gAr#/-788/64/-364/-4/0/0