It is hardcoded into the plugin in several places. I think I may have modified this before. See if you can find where someone else requested more maps to be allowed in the vote. If you can't find it after looking thoroughly then post back and I can look into it.
EDIT: I found it quickly:
http://forums.alliedmods.net/showpos...66&postcount=4
Also, using a cvar is not really an option because the plugin is not written modular enough to do so. This is the best that you are going to get. I hope you don't need more than 6.
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