Help!

Whenever I design a huge ship, installing components until i reached the max, then after saving it, the ship is like ripped of the parts of the right section. Everything I placed in the right section was missing! All the weapons, extras, modules, everything that i placed in the right part of the hull was gone. Another problem is, despite loosing some components, its size is still recognized. Even though some parts are not shown in the screen and the comonent list, its size is still added to the total size of the ship, leaving me not being able to reconstruct my design. I already tried building two seperate designs, but it just kept on happening.

Has anyone here already encountered this kind of problem? Any suggestion would be greatly appreciated. Thanks!