I am using Liferay Developer Studio Version: 2.2.2.201504240205-ga3a, and I have an existing Liferay project that is made up of multiple portlets. I have the SDK installed, and I have deployed some test portlets (with Maven/Ant). How do I create 1 war file that deploys the portlets correctly?
If your existing project is an SDK project (e.g. utilizes Ant), it's probably contained in an SDK folder. Use "Window/Preferences/Liferay/Installed Plugin SDKs" to make this SDK known to Liferay. Then just use "File/Import/Liferay Projects from Plugins SDK" to import your project.
If it's a maven plugin try if it's "File/Import/Liferay Project from existing source" or just a plain import of a maven project.