You have likely set your account to use Google's 2 step verification. If you want to log in via non-browser applications (such as Raccoon), you need to create an application specific password.
Please note: unless you intent to download payed apps, it is recommended to not use your primary account with Raccoon.
You can change Raccoon's data directory if you are using the java version by specifying the raccoon.homedir property, e.g.:
java -Draccoon.homedir=/tmp -jar raccoon.jar
In most cases, you should use a throw away account with Raccoon. However, if you need to use your main account (e.g. to download apps you previously bought), you can use Droidentify to obtain your GSF ID.
Did you enable two-step verification for your account? If so, you need to generate an app password for Raccoon.
Raccoon automatically uses the system's locale for searching apps. You can change that in your java system settings or by passing the user.locale property, e.g. by starting Raccoon as:
java -Duser.locale=de -jar raccoon.jar
Google Play does not allow anonymous downloading. You must always supply a valid account. However, you are free to use a throw away account with Raccoon. In fact, this is even recommended.
Your account data (username, password, android id) is kept in your archive in a plain text file. Everyone with access to computer can gain access to your credentials.
It is a common request that credentials.cfg should be encrypted, but since Raccoon would need to be able to decrypt the file at runtime, this would not offer any serious protection. Therefore it is strongly recommended not to use Raccoon on any computer that is not under your total control. You should also use a dedicated account with Raccoon.
Raccoon stores your credentials in a file called "credentials.cfg" in the root folder of your archive. Simply edit or delete that file.
Conceptually, or at least as far as Google Play is concerned, an archive represents a phone (or a tablet for that matter). You can create as many archives as you like (e.g. one per device you own).
Functionwise, an archive acts as a download folder that can contain multiple versions of downloaded apps and that is able to automatically update all contained apps.
In other words: think of an archive as the place on your harddisk, where you keep a backup of the apps on your phone (or tablet).
Yes! Downloading of paid apps is supported since v2.3, however: