Adsharing generating errors, please help

Hi, Ad Sharing is generating errors on my wp site and I am launching shortly. I've included the full error log here, would you mind helping me with this? I'd really appreciate it, thanks!

Deprecated: Assigning the return value of new by reference is deprecated in /home/USER/public_html/wp-content/plugins/ad-sharing/ad-sharing.php on line 44 Strict Standards: Redefining already defined constructor for class Ad_Sharing in /home/USER/public_html/wp-content/plugins/ad-sharing/ad-sharing.php on line 97 Deprecated: Assigning the return value of new by reference is deprecated in /home/USER/public_html/wp-content/plugins/ad-sharing/ad-sharing.php on line 685 Notice: register_uninstall_hook was called incorrectly. Only a static class method or function can be used in an uninstall hook. Please see Debugging in WordPress for more information. (This message was added in version 3.1.) in /home/USER/public_html/wp-includes/functions.php on line 3622 Warning: session_start(): Cannot send session cookie - headers already sent by (output started at /home/USER/public_html/wp-content/plugins/ad-sharing/ad-sharing.php:44) in /home/USER/public_html/wp-content/plugins/paid-memberships-pro/paid-memberships-pro.php on line 27 Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /home/USER/public_html/wp-content/plugins/ad-sharing/ad-sharing.php:44) in /home/USER/public_html/wp-content/plugins/paid-memberships-pro/paid-memberships-pro.php on line 27 Notice: bbp_setup_current_user was called incorrectly. The current user is being initialized without using $wp->init(). Please see Debugging in WordPress for more information. (This message was added in version 2.3.) in /home/USER/public_html/wp-includes/functions.php on line 3622 Notice: bp_setup_current_user was called incorrectly. The current user is being initialized without using $wp->init(). Please see Debugging in WordPress for more information. (This message was added in version 1.7.) in /home/USER/public_html/wp-includes/functions.php on line 3622 Notice: The called constructor method for WP_Widget is deprecated since version 4.3.0! Use __construct()

instead. in /home/shopperl/public_html/wp-includes/functions.php on line 3457 Notice: The called constructor method for WP_Widget is deprecated since version 4.3.0! Use

__construct()

instead. in /homeUSER/public_html/wp-includes/functions.php on line 3457 Notice: Undefined index: portfolio_item_slug in /home/USER/public_html/USER/plugins/thereview-plugin/post-types/portfolio-tax.php on line 56 Notice: Undefined index: video_cat_slug in /home/USER/public_html/wp-content/plugins/thereview-plugin/post-types/video-tax.php on line 44 Warning: Cannot modify header information - headers already sent by (output started at /home/USER/public_html/wp-content/plugins/ad-sharing/ad-sharing.php:44) in /home/USER/public_html/wp-includes/pluggable.php on line 1207