You can create a software input and configure it to be unitless > val-sbyte and then generate your nv and proxy it out as a boolean writable. Then link your boolean schedule to the proxy point.
If this is just for a vav or rooftop unit I prefer to use either the direct lon schedule or an enum schedule. With either one of these you would create an nviTodEvent snvt. The direct lon schedule would link straight to the Tod snvt. With the enum sched you would need to proxy out the current state, next state, and time to next state and link accordingly.
I found the easiest way to add software points is in the nv config view. Then select those points to show on wiresheet, very easy. For a boolean schedule you could use snvt "state", "switch", or "count_f" and like lwarren said select the internal format is sbyte or ubyte. Using count_f would probably be easiest 0 = unoccupied 1 = occupied. I would prefer to use the occupancy arbitrator block and link the effective occupancy to a "not" block to turn on a fan. Not sure on the details of you app though.