RockSim - Tube fin on standoff

[mjennings]

So I picked up an Estes 1:14 HoJo with the intent on upscaling a EAC Firecat. I was trying to sim it last night and using a tube fin on a pod was causing the model to not launch. I switched it to a ring fin with no supports and it worked fine. The model is stable without the tube fin. Any thoughts on if the ring fin work around is valid mathematically?

Edit: I have version 10.4