Hi, it seems your mod had touched the weak point of the gmae system. It just keeps causing various problems(bugs). but I still think it' s a extraordinary mod that could lead the tendency of the game or the game itself should consider to integrate the scale tweaking someday. I' ve got some issues about TweakScale that are happening in my game. I think that there might be someone who has already reported the similar problem to you, because it happens in the current version(1.47). So I will give it a breif describe and if it is not enough to make sense, hope you can reply me and I' ll see what more about the bug' s details that I can give you. The bugs are describe as below: By keep clicking on the scale tweaking button to switch the size of a part between two ranks, the mass of this part will simply pile up to a enormous figure. This will be recovered by correcct mass data as soon as you go for launch. Once in flight, the parts that has been tweaked can become heaver every time game loads the ship. Now I have found the stocked 2.5m-360-FuelTank(I changed it into a 3.75m one while it weights over than 200t in savefiles) and the large battery have this problem. The mod switch part' s size automaticly when part attched. It works to some parts, some not(all stocked). Sometimes tweaks it into right size, sometimes not, especially adapters. (And when I try to switch it back, the first bug happens, gaining more weight on MJ vessel information) It seems the 0.44 version does not has these problems. Hope the next release to be better.