3
I had the same problem when I downloaded and installed XoopsGallery 1.3.3.6 (tgz) (tar ball file) on 4/30/05.
I did not have the problem when downloaded xoopsgallery-1_3_3_6.zip (zip file). After checking it several times in both Linux and Windows XP, I think the tar ball file was bad, and that is why the module did not show up in Xoops/Administration Module.