I just got 50 nested IFs to work.
Here's the formula, for the masochists out there:
User.StateName = IF(Prop.StateNumber=1,"Delaware",
IF(Prop.StateNumber=2,"Pennsylvania",
IF(Prop.StateNumber=3,"New Jersey",
IF(Prop.StateNumber=4,"Georgia",
IF(Prop.StateNumber=5,"Connecticut",
IF(Prop.StateNumber=6,"Massachusetts",
IF(Prop.StateNumber=7,"Maryland",
IF(Prop.StateNumber=8,"South Carolina",
IF(Prop.StateNumber=9,"New Hampshire",
IF(Prop.StateNumber=10,"Virginia",
IF(Prop.StateNumber=11,"New York",
IF(Prop.StateNumber=12,"North Carolina",
IF(Prop.StateNumber=13,"Rhode Island",
IF(Prop.StateNumber=14,"Vermont",
IF(Prop.StateNumber=15,"Kentucky",
IF(Prop.StateNumber=16,"Tennessee",
IF(Prop.StateNumber=17,"Ohio",
IF(Prop.StateNumber=18,"Louisiana",
IF(Prop.StateNumber=19,"Indiana",
IF(Prop.StateNumber=20,"Mississippi",
IF(Prop.StateNumber=21,"Illinois",
IF(Prop.StateNumber=22,"Alabama",
IF(Prop.StateNumber=23,"Maine",
IF(Prop.StateNumber=24,"Missouri",
IF(Prop.StateNumber=25,"Arkansas",
IF(Prop.StateNumber=26,"Michigan",
IF(Prop.StateNumber=27,"Florida",
IF(Prop.StateNumber=28,"Texas",
IF(Prop.StateNumber=29,"Iowa",
IF(Prop.StateNumber=30,"Wisconsin",
IF(Prop.StateNumber=31,"California",
IF(Prop.StateNumber=32,"Minnesota",
IF(Prop.StateNumber=33,"Oregon",
IF(Prop.StateNumber=34,"Kansas",
IF(Prop.StateNumber=35,"West Virginia",
IF(Prop.StateNumber=36,"Nevada",
IF(Prop.StateNumber=37,"Nebraska",
IF(Prop.StateNumber=38,"Colorado",
IF(Prop.StateNumber=39,"North Dakota",
IF(Prop.StateNumber=40,"South Dakota",
IF(Prop.StateNumber=41,"Montana",
IF(Prop.StateNumber=42,"Washington",
IF(Prop.StateNumber=43,"Idaho",
IF(Prop.StateNumber=44,"Wyoming",
IF(Prop.StateNumber=45,"Utah",
IF(Prop.StateNumber=46,"Oklahoma",
IF(Prop.StateNumber=47,"New Mexico",
IF(Prop.StateNumber=48,"Arizona",
IF(Prop.StateNumber=49,"Alaska",
IF(Prop.StateNumber=50,"Hawaii",FALSE)
)))))))))))))))))))))))))))))))))))))))))))))))))
Of course I used VBA to generate- and stuff the formula. I'll probably publish the file as an article, as soon as I get a chance.