1) You can install the Android SDK 1.6 (run the tools / android from the Android SDK folder and download the old SDK 1.6 from the Google Repository), and Titanium will detect the Android SDK
2) As for Android SDK 2.2, adb has moved to the platform tools folder, so you will need to create a link in [your-android-sdk-folder] / tools, for example: ln -s ../ platform-tools / adb
(full instructions for non-linux are here: http://guides.appcelerator.com/en/getting_started.html )
Finally, in the Titanium Test & Package / Run emulator window, you will have a choice between Android SDK 1.6 and 2.2
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