can anyone help with this problem?

http://xoopsgallery.org/modules/newbb/viewtopic.php?topic_id=721&forum=4&post_id=2705#forumpost2705

as the developers seem busy...

Try this.

Idk if your problem has been solved, but I had a similar one. Well to the extent that gallery wouldn't show up, let alone the gallery2 bar. I went in and played around with the code and eventually got gallery2 working. Then same problem with the gallery2 bar. Upon some more playing with code, I got the darn thing to work. Feel free to try using what I have done.
try this
Although I downgraded to XOOPS 2.0.13.2 I did test this code with XOOPS 2.0.15 and it worked.