Hopefully someone's still here - had a breakthrough on this today after finishing this weekend's.
I currently have the theme, a line drawn through the right points, the two words describing the theme and the two letter change, but I believe I've either gone wrong somewhere in my extra letters or I'm not getting the final instruction from them.
I have "Draw..." then what appears to be gibberish following, and I've been staring too long to make sense of it. I'm assuming from the object indicated by the two words, it would be simply "mirror the line you've drawn to complete the image", but I'd prefer to be very sure as I could still potentially submit :)
Any help appreciated at this eleventh hour.