Fix Required for Excel Macro Program

I have a program which groups complex data. There are some steps where the program checks for overlapping year ranges. It normally works fine but after trying it on a very large file, I think the groups it create are too big (i.e. too many rows) for it to handle properly and the program cannot process them. I managed to pick out a part of the data which is resulting in an error. i have attached the macro file and a sample of the rows which are causing error. the settings to use are: Macro is Data Processing:ShowProcessForm In the form, the settings I am running on are below: Part number = col 4 Year-0 = col 5 Vital Columns = 6-12 BIDDERS: It is very important that you only bid on this project if you are sure you can fix the problem. NOTE: the program works fine, and the way it works should not be changed. We just want a solution to solve this problem when the data group is a large number of rows. We use scipe to communicate with freelancers.