Thank you for your help.
Using composer I have installed frankmullener/gallery and swipestripe/swipestripe-gallery with this result.
C:\wamp\www\limerock15bs>composer require swipestripe/swipestripe-gallery
Using version dev-master for swipestripe/swipestripe-gallery./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.
Problem 1
- Installation request for swipestripe/swipestripe-gallery dev-master -> satisfiable by swipestripe/swipestripe-gallery[dev-master].
- swipestripe/swipestripe-gallery dev-master requires frankmullenger/gallery
1.0.* -> no matching package found.
Potential causes:
- A typo in the package name
- The package is not available in a stable-enough version according to your minimum-stability setting
see <https://groups.google.com/d/topic/composer-dev/_g3ASeIFlrc/discussion> for more details.
Read <https://getcomposer.org/doc/articles/troubleshooting.md> for further common problems.
Installation failed, reverting ./composer.json to its original content.
I'm thinking it is the version of the first gallery causing the problem.