I don't think there's anyway to store them as such.
When I was at Gatwick for the last set, I didn't have internet access every day at the hotel, so at the test centre i used the free internet there to open all the databases i needed in full, put my laptop into hibernate, and they were all still open when i re-started my laptop at the hotel.
the only problem is you then don't get the Info if you don't know the answer, or the pop up annexes, so useless for Gen Nav.