Have the MainType plugin installed in InDesign (13.01 x64). When opening the options window, the window is empty. I can not choose options (see pic).
What can I do? 
The dialog is empty by design. The plugin will work without user intervention, so currently that dialog is of no use, but we have it in case we decide to add more functionality to the plugin.
Perhaps if you were to add some text stating that there are currently no options available, it would reassure users that nothing is wrong.