[Babul]

the #include <a_npc> is wrong. your script is NOT a filterscript nor a gamemode, its a NPC script - that one which gets called by the ConnectNPC() callback (from within a filter/gamemode script).
it in fact requires 2 scripts to run a NPC: 1 (filter)script, and the npc "type" itself. a busdriver, a plane etc.
read that tutorial again, iam sure you missed something tricky there.