Contact your hosting provider. Looks that problem is related to your server settings and server goes down. Also, check the server error logs, probably you have some errors that could help to find out the reason.
If you use Massive Addons server is using mod_security or FastCGI handler for PHP then you need to contact your hosting provider and ask to increase the maximum body length value.
One standard license is valid only for 1 project. Running multiple projects on a single license is a copyright violation.