Ok, i will try

only few things:
1: i must unistall gphoto and libgphoto before install hold versions?
2: if i can install hold versions, what's going on when i will launch "apt-get upgrade" and "apt-get upgrade"? Gphoto and Libgphoto will be upgrade to the last release?

For build hold versions:

1: download the hold packages from gphoto website
2: unzip packages
3: cd libgphoto2-2.5.16
4: ./configure
5: make
6: sudo make install

7: redo same steps for gphoto2-2.5.15

Correct?

Thanks

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