To use your custom XML-Attributes in a Library Project you need some special namespace, otherwise you will get a strange error in the console for your project. Instead of your package as namespace, which you would usually use, you have to use the following: http://schemas.android.com/apk/res-auto You can read more about this here.
Accessing the app SQLite database is not possible on non-rooted devices. If you want to copy it you could instead use an emulator. You then find the db in the data folder. Or you use this code to copy the whole databse-file to your external storage e.g. the SD-card.
Just as a little reminder for me and other: HOw to send an eMail with Android Intents: