It would be helpful to have an event thrown when the raddataform's  Mode Changes.

If you check the dataform's mode on BeginningEdit, it is still set to ReadOnly and has not yet changed to AddNew or Edit.

When RadDataForm is placed in a Window/RadWindow and there is a DataFormComboBoxField, if the combo value is changed, RadDataForm instance remains in the memory after the window is closed.

RadDataForm-IsReadOnly state of a TextBox is not persisted when switching implicit styles

When adding a new item through RadDataForm's UI, the ValidationSummary is sometimes unaware of existing errors and committing edit is allowed. (Required, StringLength DA attributes). It works fine on editing.