Seems so useful, but not working!

It seems like you’ve made a great plugin, and I know it works with other people but it doesn’t work for me and I don’t know why. Hopefully I can explain my problems and you’ll know what’s going wrong.

page being tested: https://imagelotus.com/upload

Everything is fine until I try to upload a file. The first file I tested was a 20mb ZIP file. The upload progress seemed fine, and when it reached 100% the page reset to a blank upload form. I went to check for the file and nothing was there though.

Now, whenever I try to upload something I’m getting an error message “Connection attempt failed!”. I’ve tested multiple filetypes (JPG, ZIP, MP3, etc.), multiple FTP accounts (including root), and I’ve set the target upload folder (root folder for a dedicated FTP account) to 777. When I attempt an upload, the progress will reach 100% before I get an error message. I’ve checked my FTP info and I’ve successfully used it to log into my site via FTP client.

What am I missing, or what am I doing wrong?