[thefirestate]

You forget to tell sscanf how big the text string should be.

You are doing this:

PHP Code:

if(sscanf(params, "iis", time, ty, msg)) return SendClientMessage(playerid, -1, "Usage: /announce [Time] [Msg Type] [TEXT]"); 


When it should be:

PHP Code:

if(sscanf(params, "iis[25]", time, ty, msg)) return SendClientMessage(playerid, -1, "Usage: /announce [Time] [Msg Type] [TEXT]"); 


Otherwise it will produce a warning.

Anyways, you've did pretty good job and the explanations you gave are detailed enough for newbies in pawn.