Here's an example of a Kerbal Space Program launch that fails due to the SRBs crashing into the rest of the stage. Launch TWR was about 1.16, TWR at breakup was 2.53, altitude was 23.3k and 690 m/s. I'm not 100% sure why this happens. It could be that TWR at burn-out is too high, or that radial linkages are just really tricky in KSP 0.25.



This next video is an example of what happens when the CoL (center of lift) is ahead of the CoM (center of mass). As soon as the angle of attack (AoA) gets above a few degrees the rocket tumbles as the lift from the nose overcomes the ability of the reaction flywheels and tail fins to counter that. One option would be to add more control fins to the SRBs at the bottom. Another option would be to change the staging so that the LV-T45 LFE runs at 1/3 power during launch to act as a control at the bottom of the rocket.



Another example of SRBs crashing into the center. This particular rocket tried to use Separatron rockets (the miniature ones pointed out at the top of the SRBs), but I'm not sure if it just made the problem worse.



If you have the Zero Point fairings mod installed, you need to be careful that your fairing around the payload is wider then the payload. I lost two of these in a row because of not using the next larger fairing when needed. Just because the nose cone will go on the rocket while in the VAB (Vehicle Assembly Building) does not mean that you do not have parts cliping through the fairing. Destruction of this sort of thing looks pretty wild and buggy as some parts stay in place.