After.cs

public override object EditValue(ITypeDescriptorContext context, IServiceProvider provider, object value)
{
    var converter = new HotkeyConverter();
    var keys = (value == null) ? Keys.None : (Keys) converter.ConvertTo(value, typeof(Keys));

    value = base.EditValue(context, provider, keys);

    return converter.ConvertFrom(value);
}

Before.cs

public override object EditValue(ITypeDescriptorContext context, IServiceProvider provider, object value)
{
    Keys keys = (value == null) ? Keys.None : (Keys)((Hotkey)value);
    object obj = base.EditValue(context, provider, keys);
    return (Hotkey)((Keys)obj);
}