It seems that Sonnb is back again. At least he updated some of his other addons for XF2.x and he is also now more regularly in his own support forum: http://www.sonnb.com/Does anyone have suggestions on how I might be able to export the data and images or whatever I may need to do in order to import it later into another solution? I need to upgrade to XF2 and this is the only thing holding me back right now...
I hope that he will communicate soon what we can expect from his Gallery addon for xenforo 2.x
But for sure this gallery addon for XF1.5x is not further developed anymore because of obvious reasons (end of life of XF 1.5x)
Just go in his support forum and ask him.