You are only allowed to bump after 2 weeks(read the rules). I haven't done with these zooms but if you wanted that user can't zoom, I guess it would be...
Code:
if(cs_get_user_zoom(id) != 1)
cs_set_user_zoom(id, 1, 0);
Edit: Oh, you wanted it with awp cvar... Then you do (with pcvars, you should use them)
Code:
new my_cvar;
public plugin_init()
my_cvar = register_cvar("awp_cvar", "1");
public function()
//When you use it here, read it like this:
new value = get_pcvar_num(my_cvar);
if(value == 1)
//do your thingys