My custom mod Spitfire was repaired from the damage on the first flight with liberal amounts of wood glue added to the paper shroud where the fins meet and around.  In this way I was creating "glue strip supports" (especially important for the fin that doesn't go all the way down to the bottom of the rocket...that one just seemed to wiggle and move the paper shroud around).  I also added a small estes chute to the top section before the nose cone and 2 sheets of wadding to protect the chute.  Lift off was good, however it was lower than expected.  The ejection happened shortly after apogee and rocket broke apart as planned; however the section just above the fins didn't separate (that one was a trouble one after the last launch due to a lot of soot and perhaps the tube connector expanding) and while the parachute did come out, it didn't open.  Regardless the parawad served it's purpose and allowed the rocket to descend bottom first and it landed down without damage.  SUCCESS!!!  I may next try a streamer in place of the parachute and I'll have to work on loosening section 2.  Great rocket and this mod is lots of fun!