diff --git a/src/de/teamteamteam/spacescooter/level/LevelConfig.java b/src/de/teamteamteam/spacescooter/level/LevelConfig.java
index f99facd..da3d15d 100644
--- a/src/de/teamteamteam/spacescooter/level/LevelConfig.java
+++ b/src/de/teamteamteam/spacescooter/level/LevelConfig.java
@@ -9,13 +9,24 @@ import de.teamteamteam.spacescooter.entity.Entity;
  * The actual LevelConfig.
  * It contains all the important details that are required to build the level up
  * and fill it with hot living action.
+ * Its attributes are read by the LevelConfigParser from the files in res/levels/*.level .
  */
 public class LevelConfig {
 
+	/**
+	 * The levels name.
+	 */
 	public String name;
+	
+	/**
+	 * The background the level will be using.
+	 */
 	public String background;
+	
+	/**
+	 * The background music this level will use.
+	 */
 	public String backgroundMusic;
-	public String bossEnemy;
 	
 	/**
 	 * Intervals have a start and an end.
@@ -50,8 +61,6 @@ public class LevelConfig {
 		sb.append(this.background);
 		sb.append(" backgroundMusic=");
 		sb.append(this.backgroundMusic);
-		sb.append(" bossEnemy=");
-		sb.append(this.bossEnemy);
 		sb.append("\\\n\tRules:\n");
 		for(int[] rule : this.spawnRuleList) {
 			sb.append("\t");
@@ -67,9 +76,17 @@ public class LevelConfig {
 	 * TODO: Catch overlapping intervals and more!
 	 */
 	public void addIntervalToList(int intervalStart, int intervalEnd) {
-		if(this.getIntervalIndexByBorders(intervalStart, intervalEnd) != -1) {
-			System.err.println("Duplicate interval - not added!");
+		if(intervalStart >= intervalEnd) {
+			throw new LevelConfigException("Interval borders are invalid! intervalStart must be < intervalEnd!");
+		} else if(this.getIntervalIndexByBorders(intervalStart, intervalEnd) != -1) {
+			throw new LevelConfigException("Duplicate interval - not added!");
 		} else {
+			if(this.intervalList.size() > 0) {
+				int[] lastIntervalInList = this.intervalList.get(this.intervalList.size() - 1);
+				if(intervalStart < lastIntervalInList[1]) {
+					throw new LevelConfigException("Intervals must be added in order!");
+				}
+			}
 			int[] newInterval= {intervalStart, intervalEnd};
 			this.intervalList.add(newInterval);
 		}
@@ -106,8 +123,7 @@ public class LevelConfig {
 	public void addEntitySpawnRule(int intervalStart, int intervalEnd, String entityName, int amount, int spawnRate) {
 		int intervalIndex = this.getIntervalIndexByBorders(intervalStart, intervalEnd);
 		if(intervalIndex == -1) {
-			System.err.println("No Interval for rule found!");
-			System.err.println("Rule: " + intervalStart + " to " + intervalEnd + ": " + entityName + ", " + amount + ", " + spawnRate);
+			throw new LevelConfigException("No Interval for rule found!\nRule: " + intervalStart + " to " + intervalEnd + ": " + entityName + ", " + amount + ", " + spawnRate);
 		} else {
 			int enemyNumber = Entity.availableNames.valueOf(entityName).ordinal();
 			int[] newRule = {intervalIndex, enemyNumber, amount, spawnRate};
diff --git a/src/de/teamteamteam/spacescooter/level/LevelConfigException.java b/src/de/teamteamteam/spacescooter/level/LevelConfigException.java
new file mode 100644
index 0000000..07a6c79
--- /dev/null
+++ b/src/de/teamteamteam/spacescooter/level/LevelConfigException.java
@@ -0,0 +1,39 @@
+package de.teamteamteam.spacescooter.level;
+
+/**
+ * RuntimeException thrown when parsing (or subsequent actions concerning the LevelConfig)
+ * go horribly wrong.
+ */
+public class LevelConfigException extends RuntimeException {
+	
+	/**
+	 * Default serial Version UID.
+	 */
+	private static final long serialVersionUID = 1L;
+	
+	/**
+	 * Message the Exception carries with it.
+	 */
+	private String message;
+	
+	
+	/**
+	 * Constructor passing on the message.
+	 */
+	public LevelConfigException(String msg) {
+		this.message = msg;
+	}
+
+	/**
+	 * Add our custom message to the Exceptions representation.
+	 */
+	@Override
+	public String toString() {
+		StringBuilder sb = new StringBuilder();
+		sb.append(this.message);
+		sb.append("\n");
+		sb.append(super.toString());
+		return sb.toString();
+	}
+	
+}
diff --git a/src/de/teamteamteam/spacescooter/level/LevelConfigParser.java b/src/de/teamteamteam/spacescooter/level/LevelConfigParser.java
index 18e72ae..e5f248d 100644
--- a/src/de/teamteamteam/spacescooter/level/LevelConfigParser.java
+++ b/src/de/teamteamteam/spacescooter/level/LevelConfigParser.java
@@ -70,10 +70,8 @@ public class LevelConfigParser {
 							this.levelConfig.background = linePieces[1];
 						} else if (linePieces[0].equals("backgroundMusic")) {
 							this.levelConfig.backgroundMusic = linePieces[1];
-						} else if (linePieces[0].equals("bossEnemy")) {
-							this.levelConfig.bossEnemy = linePieces[1];
 						} else {
-							System.err.println("[LevelConfigParser] Unknown attribute in line: '" + line + "'");
+							throw new LevelConfigException("[LevelConfigParser] Unknown attribute in line: '" + line + "'");
 						}
 					}
 					break;
@@ -91,14 +89,12 @@ public class LevelConfigParser {
 							String[] entitySpawnRule = rule[1].split(",", 3);
 							this.levelConfig.addEntitySpawnRule(this.currentIntervalStart, this.currentIntervalEnd, entitySpawnRule[0], Integer.parseInt(entitySpawnRule[1]), Integer.parseInt(entitySpawnRule[2]));
 						} else {
-							System.err.println("Unknown rule type: '"+rule[0]+"' : '"+line+"'");
+							throw new LevelConfigException("Unknown rule type: '"+rule[0]+"' : '"+line+"'");
 						}
 					}
 					break;
 				default:
-					System.err.println("[LevelConfigParser] Where am i?!");
-					this.printUnknownLine(line);
-					break;
+					throw new LevelConfigException("[LevelConfigParser] Where am i?!");
 			}
 		}
 		return this.levelConfig;
@@ -129,13 +125,4 @@ public class LevelConfigParser {
 		}
 	}
 
-	/**
-	 * Debugging method - print an unknown line read.
-	 */
-	private void printUnknownLine(String line) {
-		System.err.println("[LevelConfigParser] Unknown line?");
-		System.err.println(line);
-		System.err.println();
-	}
-	
 }
diff --git a/src/de/teamteamteam/spacescooter/screen/LoadingScreen.java b/src/de/teamteamteam/spacescooter/screen/LoadingScreen.java
index 0cc67f1..e2af7c7 100644
--- a/src/de/teamteamteam/spacescooter/screen/LoadingScreen.java
+++ b/src/de/teamteamteam/spacescooter/screen/LoadingScreen.java
@@ -42,7 +42,7 @@ public class LoadingScreen extends Screen {
 	protected void paint(Graphics2D g) {
 		g.setColor(new Color(0,0,120));
 		g.fillRect(0, 0, GameConfig.windowWidth, GameConfig.windowHeight);
-		g.setColor(new Color(255,255,255));
+		g.setColor(Color.WHITE);
 		g.setFont(new Font("Monospace", 0, 50));
 		g.drawString("Loading ...", 100, 100);
 		g.drawString("Progress: " + this.getProgress() + "%", 200, 500);