A current limitation of the official Facebook API is that only a maximum of 400 photos will be retrieved when tagged photos are requested.
Users and pages have the option to restrict the type of data that is available to an application making requests on behalf of a user. This may prevent PhotoGrabber from downloading all photos that are visible to a user on the Facebook website.
An alternative that may help you is provided by Facebook.
The option to download Complete comment/tag data may cause PhotoGrabber to hang or run for extended periods of time. An example would be the George Takei's Timeline album which has many thousands of comments and likes. After 8 hours of execution, only a fraction of the metadata was downloaded causing the application to crash.