More concurrency fixes + Zombify + BPQ available

Fixed some inconsistencies due to race conditions in the project, added
Zombify monster effect, made BPQ available and some minor patches.

wz/Item.wz/Etc/0400.img.xml

@@ -9646,6 +9646,7 @@
       </canvas>
       <int name="price" value="1"/>
       <int name="slotMax" value="200"/>
+      <int name="quest" value="1"/>
     </imgdir>
   </imgdir>
   <imgdir name="04002000">