Hi,
I am sorry you are in trouble now.

You would better to check the netlist connect via design manager press CTRL+D , https://easyeda.com/Doc/Tutorial/schematic.htm#DesignManager

If you can't fix it.
You can flow the bellow steps

1. create a public project
2. just keep the sub circuits which contains the problem four-position terminal part and delete other parts, so your key job is private.
3. tell us when you done 1. and 2.

we will check your public schematic and tell you the solution, it is maybe a bug , or you bad Operation.

Thanks.

It appears that the nets just don't reliably connect to wires. I have discovered that if I move a part and then move it back to the same position, save, and then reimport to pcb, it will capture the net changes.

Also, sometimes a part will become slightly off grid, and the wires will not connect properly. This happens sometimes in schematic view if you rotate a part.

Thanks,
Colin

It is great that you can find the problem.

If you set the grid to snap, EasyEDA will keep the pin in grid all the time. We are like to know how to reproduce this opreation.

Thanks.