Wow! You have a really low file size limit for PHP uploads. This link ( https://premium.wpmudev.org/blog/increase-memory-limit/ ) will show you how to fix it. Probably set the PHP upload size to 50M would be handy for various things.
Or, alternatively, you can simply unzip the Pro zip file, and upload it into your /wp-content/plugins/ folder and then activate it through the plugins page once it uploads.
Cheers
Ben