Thank you so much, you are the best! Great response, and perfect help. Mod is amazing. Thanks.You need to change this:
rndSel=floor(random 49); //select random number 0-49, then set loc based on the case number
So it is random(13);
as you have changed the number of cases - it's trying to pick a case between 1-49, and you only have 13 cases.