The option for showing captions was not working, but a few hours after a mail to the developper, I got an answer that it we'll be done, and a day after, I had a new version doing it. Splendid support and really very useful module and plug-in !
I tried all of the Flickr plug-ins and this one is the best.
2 problems... In the PDF doc, it says you must use stream to get the content of a specific user but the command is user !
Then I never found a way to sort images by more than one tag. If there's a way, I'll be more than happy to learn it !