May have found an solution to this one and some others which seem to have the same cause.
Unknown variable l_bullet
Unknown variable image_angle
Unknown variable l_owner
Unknown variable l_syshp
Unknown variable l_cm1
Basically I got a continuous stream of these related to various sections, weapons, etc. etc. These seem to be caused by saving in SM whilst trigger lines, parenting lines etc. are disabled. I was experimenting with various things to try and find the problem and noticed it didn't happen when I hadn't turned lines off. Hope this works for you too, unless you're entering your ship in limited realism in the BP in which case ignore everything I just said, there is no solution, your ship will never work
![Wink :wink:](./images/smilies/icon_wink.gif)