Hi Sakai, Using the pictures you posted I've recreated your rocket as best I could and then tried to fly it. First thing I noticed was that those four SRBs are overkill. At 1000m the thing was going way too fast. Even with the main engine at 0 throttle. Without struts everything under the fairings does wobble too. So I took off two of the SRBs, ran struts from the second stage tank to the fairing base. It flew, I got it in orbit, USI parts and all. Had to be real careful pitching over though. I'd ditch the RCS thank and thruster on the fist stage altogether. Maybe put an SAS where the RCS tank was. Use a shorter 2.5m tank on the second stage. Procedural fairing are a a little bit easier to the use then the KW ones. If I can get some time tonight I'll work with your rocket some more. Take some screenies and send you a .craft file.