Internal Errors and using the DlgListBoxArray

I have been working on a script that allows for tagging, so I have dialogs that allow the user to select the field that contains the different information, first the user will get the file and then I populate the drop downs using the DlgListBoxArray.

When I was trying to run the script I kept getting internal errors at strange places, I could run the script once, have an error, run it again and not have an error.  Also sometime the errors where at the line where I was having a msgBox, it didn't make any sense and it was driving me nuts, probably wasted a day just trying to figure out why this wasn't working.  Well I finally noticed that one of my ListBoxs for the dialog didn't not have a default array which it needs to have.  When I put a default array in the internal errors stopped so this was the problem.  The only thing is that the error was not consistent or was happending in different places, the only way I caught this was when I noticed I had forgetten to add the default.  So if you have drop down in your dialogs and are getting internal errors that don't make any sense I recommend you check to see if all your list box have default arrays.