Ok,
I just checked weapon drop on my server and it seems to be working all the time.
Do you have any plugins that would make the npc fall wounded?
Failing that, the only reason I can see weapon drop not working is if you happen to kill them in the middle of them changing weapons,
but 30% of the time? That seems unlikely.
The radio issue has been fixed in the upcoming next update.
BotNamePrefix - I just tested, setting the prefix to "NPC" and it worked without issue.
Is there any possibility you had the formatting wrong? It's just a string so - "BotNamePrefix": "Prefix goes here",
For any areas where your npcs aren't spawning, keep an eye on console to see if it's telling you "Failed to get enough spawnpoints at..." or similar.
Some monuments are awkward, such as the Dome, and require the radius to be increased, unless you're using custom spawn points.
Regarding day/night respawn times - I've addressed this, and it will sorted in the next update.
They'll despawn/respawn much more quickly as day/night changes, if applicable.
I heard BotReSpawn npcs fight ZombieHorde npcs - I'll see about adding an option to prevent that in the near future.
If I missed anything there, or this doesn't answer something, please just let me know!
Edit* Respawn_Timer, and other timers, are minutes, however the new system works differently in that it checks how many npcs are missing every X minutes - your respawn timer, and, if it needs to, spawns some.
sS yes...it's possible for an npc to respawn more quickly than the timer duration.
Thanks.