I recently committed the following change to the Development Version of FeedWordPress:
Features and fixes roll-up from Github / FIXES: replace default wp_ table name prefix by a variable, per bug reports from users, causing problems when users had an alternate table name prefix; FEATURES: AJAXy Test Expression button to allow live testing, try to better indicate options for Trashing/Erasing a syndicated post.
This change will be part of the next public release of FeedWordPress. Interested? Curious? You can check out the details at the WordPress plugin repository ...