(I looked around for answers to these, and I struck out, so I'll ask here.) 1. My spacecraft has a slow, but annoying, roll, both on takeoff and in space. I can null the roll out with "q" and "e", but it just slowly comes back. I don't see anything that would be applying force. I keep thinking "roundoff errors" but that seems unlikely. (Is this a "barbecue roll"? A Gemini VIII stuck thruster? *grin*) 2. Is there a mod to gather launch data? For example, something that tells me each second, from launch, how many seconds from liftoff, total mass at that time, speed at that time, fuel left at that time? BONUS: Is there a mod that writes these numbers to disk? I see one, but this would be my first mod install, and I'm not sure I understand how to add a mod! 3. Is there an easy way to find out a rocket's mass? Sure, I can add up the mass numbers from the table of parts-masses, but is there a quick way? (I'm imagining something like CTRL-A to Select All, then select "Mass". You get the idea). 4. The "autopilot" isn't able to keep my rocket pointed straight up during launch. I have to manually correct it. I have to catch it fairly quickly or the rocket will "spin out". I have 8 KR-2L engines symmetrically around the center axis at the bottom, a stack of four S3-1440 (biggest) fuel tanks (two to feed first stage), then a single KR-2L as 2nd stage, then two more to feed 2nd stage, and then electricity/reactant/stabilizer, then the pod. Is this just the limit to what it'll handle? 5) I'm having a fair amount of trouble with subassemblies. I'm trying for a "stage zeroth" at the very bottom of the rocket. However, the central fuel tank I want to attach to doesn't have a "green bubble" to say it's attachable, and won't attach. Other things can attach to the center tank, but it is not interested in the central fuel tank for the stage zeroth. I haven't locked the stages, I'm not in docking mode, I have a command pod, mouse isn't hovering over staging/editor, I'm not in time warp. I have plenty of electricity and reaction propellant. I've tried deleting, re-downloading, and installing. Many thanks! This is a lot of questions. Thanks, Dave p.s. I'm unfamiliar with this forum software, and how to add a picture, or I would have; so far, no luck.