Problem resizing slots

There are several unique issues with the various slots. Here are some of the things that I saw:

1. Slots must be made up of only lines. I saw at least one slot where one side was actually a curve.
2. Some of the slots have two very tightly spaced nodes at the corners. Delete the extraneous nodes.
3. I found one oddly formed slot where one corner of the slot had 2 overlapping nodes.
You can easily cleanup all of these issues by going to Edit->Optimize selected shapes and doing a very conservative “Fit shapes to lines”. That should cleanup most of the slots without distorting the shape too much.