I also haven't idea about some categories and leave them blank. I guess it's more OK than nominating some random members.
I am having the same issue. For now I just left some categories blank and will eventually fill them up when/if I figure out who is the most deserving. Or maybe I am taking this too seriously. 
I'm having the same issue, therefore I'm wondering if there's any way someone might skip some categories because I have no idea who or what to place as event of the year/fail event of the year. Is it necessary to fill up all of the categories?