To update Simple version you can easily via Plugins section and clicking Update link.
But if you have the Pro version, the procedure is a little more complicated.
Please DO MAKE BACKUP before update. This is a must for those who customized the plugin as you will have to transfer the changes to the new version.
You should override the file with the plugin via ftp. Get to your website via cpanel and open the folder with your website and then go to content folder:
Then open plugins folder:
Upload to this folder file with a new version and extract it there:
If you are using the version 2.0 and higher, you can just delete the previous version and install the new one.
If you face with any issues, contact us and we will help you with this procedure!