Let me try to fix the bug.
It is rather complex now and unreasonable to ask u to debug it. :)
I have a splitring function now that is difficult to implement without understanding all the codes.
I think I need to invent another way for the electrons to be control instead of using only sign as a means of changing the current n electron .
I will try to add a new variable to the checkbox to control the electron sign.

You can download any older jar it should have all the files there.