Thank you for bringing this request to our attention. Maybe this topic from BuddyPress will help solve this as it seems to answer the same concern: Open internal links in activity stream in new window.
Please note that this issue is related with the customization of a third party plugin, not with the use of your theme. As theme authors, the installation, setting or debugging of third party plugins isn’t part of the support we will provide.
To go further, we invite you to ask for more help from the plugin authors and post your request on their support forums: BuddyPress support
We remain available for all support requests related with the use of your theme.