Базовая логика готова. Необходимо почистить код и свериться с требованиями.

Locomotive/Locomotive/DrawningLocomotive.cs

@@ -38,6 +38,21 @@ namespace Locomotive
             _locomotiveHeight = locomotiveHeight;
         }
 
+        public void SetBaseColor(Color color)
+        {
+            if (Locomotive is EntityWarmlyLocomotive)
+            {
+                var locomotive = Locomotive as EntityWarmlyLocomotive;
+                if (locomotive is not null)
+                {
+                    locomotive = new EntityWarmlyLocomotive(locomotive.Speed, locomotive.Weight, color, locomotive.ExtraColor, locomotive.Pipe, locomotive.FuelStorage);
+                    Locomotive = locomotive;
+                    return;
+                }
+            }
+            Locomotive = new EntityLocomotive(Locomotive.Speed, Locomotive.Weight, color);
+        }
+
         /// Установка позиции локомотива
         public void SetPosition(int x, int y, int width, int height)
         {

Locomotive/Locomotive/DrawningWarmlyLocomotive.cs

@@ -14,6 +14,16 @@ namespace Locomotive
             Locomotive = new EntityWarmlyLocomotive(speed, weight, bodyColor, extraColor, pipe, storage);
         }
 
+        public void SetExtraColor(Color color)
+        {
+            var LocomotiveWarmly = Locomotive as EntityWarmlyLocomotive;
+            if (LocomotiveWarmly is not null)
+            {
+                LocomotiveWarmly = new EntityWarmlyLocomotive(LocomotiveWarmly.Speed, LocomotiveWarmly.Weight, LocomotiveWarmly.BodyColor, color, LocomotiveWarmly.Pipe, LocomotiveWarmly.FuelStorage);
+                Locomotive = LocomotiveWarmly;
+            }
+        }
+
         public override void DrawTransport(Graphics g)
         {
             if (Locomotive is not EntityWarmlyLocomotive warmlyLocomotive)

Locomotive/Locomotive/FormLocomotiveConfig.Designer.cs

@@ -267,6 +267,7 @@
             this.labelDopColor.Text = "Extra Color";
             this.labelDopColor.TextAlign = System.Drawing.ContentAlignment.MiddleCenter;
             this.labelDopColor.DragDrop += new System.Windows.Forms.DragEventHandler(this.labelDopColor_DragDrop);
+            this.labelDopColor.DragEnter += new System.Windows.Forms.DragEventHandler(this.labelDopColor_DragEnter);
             // 
             // labelBaseColor
             // 
@@ -297,6 +298,7 @@
             this.buttonAdd.TabIndex = 2;
             this.buttonAdd.Text = "Add";
             this.buttonAdd.UseVisualStyleBackColor = true;
+            this.buttonAdd.Click += new System.EventHandler(this.buttonAdd_Click);
             // 
             // buttonCancel
             // 

Locomotive/Locomotive/FormLocomotiveConfig.cs

@@ -14,6 +14,25 @@ namespace Locomotive
     {
         DrawningLocomotive _locomotive = null;
 
+        private event LocomotiveDelegate eventAddLocomotive;
+
+        public void AddEvent(LocomotiveDelegate ev)
+        {
+            if (eventAddLocomotive == null)
+            {
+                eventAddLocomotive = new LocomotiveDelegate(ev);
+            }
+            else
+            {
+                eventAddLocomotive += ev;
+            }
+        }
+        private void buttonAdd_Click(object sender, EventArgs e)
+        {
+            eventAddLocomotive?.Invoke(_locomotive);
+            Close();
+        }
+
         public FormLocomotiveConfig()
         {
             InitializeComponent();
@@ -25,6 +44,9 @@ namespace Locomotive
             panelWhite.MouseDown += PanelColor_MouseDown;
             panelYellow.MouseDown += PanelColor_MouseDown;
             panelBlue.MouseDown += PanelColor_MouseDown;
+
+            // ! - TODO buttonCancel.Click with lambda
+            buttonCancel.Click += (object sender, EventArgs e) => Close();
         }
 
         private void labelObject_MouseDown(object sender, MouseEventArgs e)
@@ -87,13 +109,38 @@ namespace Locomotive
         }
 
         private void labelBaseColor_DragDrop(object sender, DragEventArgs e)
+        {
+            // ! - TODO Call method from object _car and set color
+
+            _locomotive.SetBaseColor((Color)e.Data.GetData(typeof(Color)));
+            DrawLocomotive();
+
+        }
+        private void labelDopColor_DragEnter(object sender, DragEventArgs e)
         {
             // ! - TODO
+
+            if (e.Data.GetDataPresent(typeof(Color)))
+            {
+                e.Effect = DragDropEffects.Copy;
+            }
+            else
+            {
+                e.Effect = DragDropEffects.None;
+            }
         }
 
         private void labelDopColor_DragDrop(object sender, DragEventArgs e)
         {
             // ! - TODO
+            if (_locomotive is DrawningWarmlyLocomotive)
+            {
+                var locomotive = _locomotive as DrawningWarmlyLocomotive;
+                locomotive.SetExtraColor((Color)e.Data.GetData(typeof(Color)));
             }
+            DrawLocomotive();
+
+        }
+
     }
 }

Locomotive/Locomotive/FormMapWithSetLocomotives.cs

@@ -87,7 +87,7 @@ namespace Locomotive
         /// Добавление объекта
         private void buttonAddLocomotive_Click(object sender, EventArgs e)
         {
-            if (listBoxMaps.SelectedIndex == -1)
+            /*if (listBoxMaps.SelectedIndex == -1)
             {
                 return;
             }
@@ -104,8 +104,34 @@ namespace Locomotive
                 {
                     MessageBox.Show("Failed to add object");
                 }
+            }*/
+
+            var formCarConfig = new FormLocomotiveConfig();
+            // TODO Call method AddEvent from formCarConfig
+            formCarConfig.AddEvent(new (AddLocomotive));
+            formCarConfig.Show();
         }
+
+        private void AddLocomotive(DrawningLocomotive locomotive)
+        {
+            if (listBoxMaps.SelectedIndex == -1)
+            {
+                return;
             }
+
+            if (_mapsCollection[listBoxMaps.SelectedItem?.ToString() ?? string.Empty] + new DrawningObjectLocomotive(locomotive) != -1)
+            {
+                MessageBox.Show("Object added");
+                pictureBox.Image = _mapsCollection[listBoxMaps.SelectedItem?.ToString() ?? string.Empty].ShowSet();
+            }
+
+            else
+            {
+                MessageBox.Show("Failed to add object");
+            }
+
+        }
+
         /// Удаление объекта
         private void buttonRemoveLocomotive_Click(object sender, EventArgs e)
         {

Locomotive/Locomotive/LocomotiveDelegate.cs

@@ -0,0 +1,10 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Locomotive
+{
+    public delegate void LocomotiveDelegate(DrawningLocomotive locomotive);
+}