I have a working solution atm, that is build with no 3rd party add ons or what so ever, but i took the wrong step while i did it and now i need to rebuild the gallery totally. It will include about from 100 even to 500 images that are in 3 different sizes. Original, thumbs and medium. Images also (originals) should be available for DL as ZIP-files from categories or galleries but it should show up only to certain group. I also might try to build a system that allows to pick images and then somehow system ZIPs them for to download.
Most of the things i have done and tested but havent got anything out to live yet cos my skills arent that good and i think i need one or more commercial solutions to make all this to happen so, that it will work with all the major browsers both in mac and pc.
So if anyone of you have made similar image gallery or you have an idea how i can build this, please hit me with links and ideas, any helps would be more than welcome, thanks.