Not uploading

I saw your post that you are not really supporting this plugin anymore, but I am really hoping that you can help me. This is a great plugin that I wish you would continue to support. I have the most recent version of gravity forms. When I try and upload the file, nothing happens. The browser looks as if it is doing something, but after 5 mins nothing uploads. Do you have any suggestions? This plugin is part of a big project for a client that has an event this weekend.
PS: I tried on the live site and installed it on a test site, and it is still not working. Maybe issue with my document? I saved as csv and tried ms csv.

PS: I am happy to make a donation

https://www.ads-software.com/plugins/gravity-forms-mass-import/