Ilogic - need help with "Case"

Hi

I have made a Part and added some ILogic code, if i change the length of the Part the numbers of holes change, as you can see in the picture:

The problem is, if i click on the red cross to close the window without selecting any value the Part disappear

What I have to add at my code to solve the problem? I know that with Case we usually use Default, but it does not work in my code

Here is the code:

longueur = InputListBox("Prompt", MultiValue.List("longueur"), longueur, Title := "Faouweb", ListName := "List")

Select Case longueur
Case  24.64
   d20 = 2
Case  37.3
   d20 = 3
Case  88.2
   d20 = 7 


End Select

iLogicVb.UpdateWhenDone = True

The file is bellow.

Thank you

Part1.zip