When adding additional shipsets, in the dropdown box to select them when customizing a race, eventually it goes off the screen. It needs a scroll bar.
You only need one mod to demonstrate this bug:
Race Mod
This adds the max amount the UI can support, if you add one more from any race it goes off the screen in the dropdown box and isn't selectable. I am using a high res monitor so its not the res: 1920x1080.
You might say not a big deal, well not really when you consider stardock are planning to add races.