Begin launcher in Swing. This, surprisingly, is the easy part, because I'm not trying to do it in C#.

.classpath

@@ -12,5 +12,6 @@
 			<attribute name="maven.pomderived" value="true"/>
 		</attributes>
 	</classpathentry>
+	<classpathentry kind="lib" path="forms-1.3.0.jar" sourcepath="forms-1.3.0-src.zip"/>
 	<classpathentry kind="output" path="target/classes"/>
 </classpath>

src/net/mosstest/launcher/GUIClientsideLauncher.java

@@ -0,0 +1,161 @@
+package net.mosstest.launcher;
+
+import java.awt.BorderLayout;
+import java.awt.EventQueue;
+import java.awt.GridLayout;
+import java.util.ArrayList;
+
+import javax.swing.JButton;
+import javax.swing.JFrame;
+import javax.swing.JPanel;
+import javax.swing.JTabbedPane;
+import javax.swing.JTable;
+import javax.swing.ListSelectionModel;
+import javax.swing.UIManager;
+import javax.swing.UnsupportedLookAndFeelException;
+import javax.swing.table.AbstractTableModel;
+
+public class GUIClientsideLauncher {
+
+	public class SingleplayerListEntry {
+
+		public String name;
+		public String description;
+		public String gamePreset;
+
+		public SingleplayerListEntry(String name, String description,
+				String gamePreset) {
+			this.name = name;
+			this.description = description;
+			this.gamePreset = gamePreset;
+		}
+
+	}
+
+	private JFrame frame;
+	private JTable table;
+
+	/**
+	 * Launch the application.
+	 */
+	public static void main(String[] args) {
+		try {
+			UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
+		} catch (ClassNotFoundException | InstantiationException
+				| IllegalAccessException | UnsupportedLookAndFeelException e1) {
+			System.out
+					.println("[ERROR] [NONFATAL] [GUI] System Look-And-Feel could not be set; falling back to default L&F.");
+		}
+		EventQueue.invokeLater(new Runnable() {
+			public void run() {
+				try {
+					GUIClientsideLauncher window = new GUIClientsideLauncher();
+					window.frame.setVisible(true);
+				} catch (Exception e) {
+					e.printStackTrace();
+				}
+			}
+		});
+	}
+
+	/**
+	 * Create the application.
+	 */
+	public GUIClientsideLauncher() {
+		initialize();
+	}
+
+	/**
+	 * Initialize the contents of the frame.
+	 */
+	private void initialize() {
+		this.frame = new JFrame();
+		this.frame.setBounds(100, 100, 800, 480);
+		this.frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+
+		JTabbedPane tabbedPane = new JTabbedPane(JTabbedPane.TOP);
+		this.frame.getContentPane().add(tabbedPane, BorderLayout.CENTER);
+
+		JPanel singleplayerTab = new JPanel();
+		tabbedPane.addTab("Singleplayer", null, singleplayerTab, null);
+		singleplayerTab.setLayout(new BorderLayout(0, 0));
+
+		JPanel singleplayerControlBtns = new JPanel();
+		singleplayerTab.add(singleplayerControlBtns, BorderLayout.SOUTH);
+		singleplayerControlBtns.setLayout(new GridLayout(0, 4, 0, 0));
+
+		JButton btnPlaySingleplayer = new JButton("Play");
+		singleplayerControlBtns.add(btnPlaySingleplayer);
+
+		JButton btnNewSingleplayer = new JButton("New...");
+
+		singleplayerControlBtns.add(btnNewSingleplayer);
+
+		JButton btnSettingsSingleplayer = new JButton("Settings...");
+		singleplayerControlBtns.add(btnSettingsSingleplayer);
+
+		JButton btnDelete = new JButton("Delete...");
+		singleplayerControlBtns.add(btnDelete);
+
+		this.table = new JTable();
+		this.table.setModel(new SingleplayerListTableModel());
+		this.table.getColumnModel().getColumn(0).setPreferredWidth(90);
+		this.table.getColumnModel().getColumn(1).setPreferredWidth(256);
+		this.table.getColumnModel().getColumn(2).setPreferredWidth(104);
+		this.table.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
+		singleplayerTab.add(this.table, BorderLayout.CENTER);
+	}
+
+	class SingleplayerListTableModel extends AbstractTableModel {
+		private String[] columnNames = { "World name", "Description",
+				"Game preset" };
+		private ArrayList<SingleplayerListEntry> entries = new ArrayList<>();
+
+		public int getColumnCount() {
+			return this.columnNames.length;
+		}
+
+		public int getRowCount() {
+			return this.entries.size();
+		}
+
+		public String getColumnName(int col) {
+			return this.columnNames[col];
+		}
+
+		public Object getValueAt(int row, int col) {
+			SingleplayerListEntry entry = this.entries.get(row);
+			switch (col) {
+			case 0:
+				return entry.name;
+			case 1:
+				return entry.description;
+			case 2:
+				return entry.gamePreset;
+			default:
+				return null;
+			}
+		}
+
+		/*
+		 * All entries are strings *at the moment*.
+		 */
+		public Class getColumnClass(int c) {
+			return String.class;
+		}
+
+		/*
+		 * Don't need to implement this method unless your table's editable.
+		 */
+		public boolean isCellEditable(int row, int col) {
+			// Note that the data/cell address is constant,
+			// no matter where the cell appears onscreen.
+			if (col < 2) {
+				return false;
+			} else {
+				return true;
+			}
+		}
+
+	}
+}

src/net/mosstest/launcher/GUIWorldCreationDialog.java

@@ -0,0 +1,103 @@
+package net.mosstest.launcher;
+
+import java.awt.BorderLayout;
+import java.awt.FlowLayout;
+
+import javax.swing.JButton;
+import javax.swing.JComboBox;
+import javax.swing.JDialog;
+import javax.swing.JLabel;
+import javax.swing.JPanel;
+import javax.swing.JTextField;
+import javax.swing.border.EmptyBorder;
+
+import com.jgoodies.forms.factories.FormFactory;
+import com.jgoodies.forms.layout.ColumnSpec;
+import com.jgoodies.forms.layout.FormLayout;
+import com.jgoodies.forms.layout.RowSpec;
+
+public class GUIWorldCreationDialog extends JDialog {
+
+	private final JPanel contentPanel = new JPanel();
+	private JTextField nameField;
+	private JComboBox<String> comboBox;
+	private JTextField inputDesc;
+
+	/**
+	 * Launch the application.
+	 */
+	public static void main(String[] args) {
+		try {
+			GUIWorldCreationDialog dialog = new GUIWorldCreationDialog();
+			dialog.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
+			dialog.setVisible(true);
+		} catch (Exception e) {
+			e.printStackTrace();
+		}
+	}
+
+	/**
+	 * Create the dialog.
+	 */
+	public GUIWorldCreationDialog() {
+		setBounds(100, 100, 450, 159);
+		getContentPane().setLayout(new BorderLayout());
+		this.contentPanel.setBorder(new EmptyBorder(5, 5, 5, 5));
+		getContentPane().add(this.contentPanel, BorderLayout.CENTER);
+		this.contentPanel.setLayout(new FormLayout(new ColumnSpec[] {
+				FormFactory.RELATED_GAP_COLSPEC,
+				FormFactory.DEFAULT_COLSPEC,
+				FormFactory.RELATED_GAP_COLSPEC,
+				ColumnSpec.decode("default:grow"),},
+			new RowSpec[] {
+				FormFactory.RELATED_GAP_ROWSPEC,
+				FormFactory.DEFAULT_ROWSPEC,
+				FormFactory.RELATED_GAP_ROWSPEC,
+				FormFactory.DEFAULT_ROWSPEC,
+				FormFactory.RELATED_GAP_ROWSPEC,
+				FormFactory.DEFAULT_ROWSPEC,}));
+		{
+			JLabel lblWorldName = new JLabel("World name:");
+			this.contentPanel.add(lblWorldName, "2, 2, right, default");
+		}
+		{
+			this.nameField = new JTextField();
+			this.contentPanel.add(this.nameField, "4, 2, fill, default");
+			this.nameField.setColumns(10);
+		}
+		{
+			JLabel lblDescription = new JLabel("Description:");
+			this.contentPanel.add(lblDescription, "2, 4, right, default");
+		}
+		{
+			this.inputDesc = new JTextField();
+			this.contentPanel.add(this.inputDesc, "4, 4, fill, default");
+			this.inputDesc.setColumns(10);
+		}
+		{
+			JLabel lblGameProfile = new JLabel("Game profile:");
+			this.contentPanel.add(lblGameProfile, "2, 6, right, default");
+		}
+		{
+			this.comboBox = new JComboBox<String>(); //todo pass array in with set of games.
+			this.contentPanel.add(this.comboBox, "4, 6, fill, default");
+		}
+		{
+			JPanel buttonPane = new JPanel();
+			buttonPane.setLayout(new FlowLayout(FlowLayout.RIGHT));
+			getContentPane().add(buttonPane, BorderLayout.SOUTH);
+			{
+				JButton okButton = new JButton("OK");
+				okButton.setActionCommand("OK");
+				buttonPane.add(okButton);
+				getRootPane().setDefaultButton(okButton);
+			}
+			{
+				JButton cancelButton = new JButton("Cancel");
+				cancelButton.setActionCommand("Cancel");
+				buttonPane.add(cancelButton);
+			}
+		}
+	}
+
+}