read more link?

This is almost the perfect plug in I needed with one exception. Is there a way to utilize the native <!--more--> tag for displaying partial posts? I tried to add $more_link_text, $stripteaser in the code, specifically in the GetFullContent area, like shown here: http://codex.ww.wp.xz.cn/Function_Reference/get_the_content but it did not work.

Any ideas?

https://ww.wp.xz.cn/plugins/onespace-lastpost/