Difficulty in Importing My Map Files

Hello,
I am finding it difficult to import my map files. Once I have made a map on my computer using a CSV file and save it I can reload the .map easily.
But when I give the same file to a different user I get the following message:
Error Line 5489 Invalid property index Screenshot:
I need a quick fix to this because my client is considering in purchasing the software and if I don't solve this they may move onto something else. Any idea on how to solve this?
Thanks!!
