found this:

“Application Load Error 5:0000065434” tends to occur if the game installation is not in the same folder as the Steam installation.

This has nothing to do with your map,
try reinstalling the game and see if it works.
 
or try this:

you can fix this error by linking the game files to Steam using Command Prompt or placing a copy of Steam.exe in the game's destination folder.

Zombies do nothing after spawning from the second spawner, I tried making a new map but still stuck with the same problem.
 
zombie spawner:
targetname: start_zone_spawners
script_noteworthy: zombie_spawner
script_forcespawn: 1
count: 9999
spawnflags: 3
 
 
zone:
targetname: start_zone
target: start_zone_spawners