I am having a similar problem.
4.75 patched through to 4.91.
When I open the Galactic Map, all the other stars I have jumped to are stacked on top of each other. Sol is off to one side, but the 'sun' icon overlaps with the other 'star' icons.
I can zoom in and out, and, by dragging a rectangle over them with the mouse, select the lot, but cannot move then.
If I use the 'line up' button, then they all stack on top of one another.
When I open the Galactic window, I get a series of errors, missing files etc (I am away from home atm, and will post details later), but then the window opens succesfully, although with the problems outlined above.
I get a similar series of errors with the
System View window, but then it fails to open and forces the game to quit.
My first thought is to try a fresh 4.91 install, and then to copy the 'Steve' database over again, as that appears to be the saved game location?