Updated Custom campaigns (markdown)

Custom-campaigns.md

@@ -152,6 +152,38 @@ Correct:
         - VMFA-251
 ```
 
+#### 'Cannot find ControlPoint named Carrier'
+
+![image](https://user-images.githubusercontent.com/89945461/133664442-823d7841-1bc6-43b6-a733-cc157232ec38.png)
+
+Incorrect:
+```
+# Stennis object in the .miz file is called "Blue CV"
+  Carrier:
+    - primary: BARCAP
+      secondary: air-to-air
+      aircraft:
+        - F-14B Tomcat
+    - primary: BARCAP
+      secondary: any
+      aircraft:
+        - F-14B Tomcat
+```
+
+Correct:
+```
+# Stennis object in the .miz file is called "Blue CV"
+  Blue CV:
+    - primary: BARCAP
+      secondary: air-to-air
+      aircraft:
+        - F-14B Tomcat
+    - primary: BARCAP
+      secondary: any
+      aircraft:
+        - F-14B Tomcat
+```
+
 ## Designing campaigns in the mission editor
 
 When creating a campaign it may be easiest to start with an existing campaign in the same theater and modify it to suit your needs. If starting from scratch, ensure that Combined Joint Task Forces Blue and Combined Joint Task Forces Red are assigned to the blue and red coalitions respectively, as these will be used to define many of the campaigns properties.