If you add additions properties to Editorbutton descendant, it doesn't serialize properly into Designer.cs.
Editorbutton descendant doesn't serialize correctly
Answers approved by DevExpress Support
We have discussed this issue with our developers and decided that this behavior isn't a bug. To serialize EditorButton descendants, add new constructors with your custom properties and all variations of common properties that you want to change via the designer. For instance, you can simply create a new constructor based on the largest one and add additional parameters corresponding to your custom properties. Please note that it is also required to add the [EditorButtonPreferredConstructor] attribute to this constructor.
The attached project demonstrates this approach.