Well lets take each one specifically
1. I can not speak specifically on Invision Gallery but my understanding is it has a very limited feature set compared with our product. Now I can tell you how our program operates. It uses the invisionboard login and you are able to load the stylesheet calls from invisionboard over photopost. You would still need to make whatever header and footer to load over photopost.
2. No
3. There is no such convertor that I know of.
4. As noted above YES but all skins must be exported as files and be in the style_images directory which is the Invision default directory to export stylesheets to.
5. You can search by title, description, all fields(all search photos table fields like extra fields keywords), comments, username, date range, specific category or multiple cats or all and whether it contains at least one word or all words on a multiple word entry search
6. This would be an invisionboard hack to mod the forum templates
7. You can search our modifications forum and see if someone has written one for invisionboard. I do beleive there is one such animal in those sections for invision
8. INTEGRATED LOGIN
9. You can move images between cats or albums there is a move box when viewing the photo as admin and a user can edit a photo and there will be a cat move box to move the photo if you allow moving of photos
10. Administration permissions is based on usergroups so you can set who can do what
11. Yes there is private albums and public ones and the admin can choose to allow albums or not allow albums per usergroup.
12 YES
13. There is like so many PHP scripts no trial version since once you have the code you have it sorry.
14. You can set per usergroup the following restrictions.
a. upload limit per day number of images
b. Maximum allowable filesize
c. Max diskspace they can use
15. A members gallery link is in this format
http://www.photopost.com/photopost/s...user=1&cat=500
here is the member gallery link
http://www.photopost.com/photopost/s...ry.php?cat=500
16. You can assign albums to cats in our program but on our showgallery page the images are set in there own place not scattered with the cat images
17. If you give moderators permission to delete images then they can. Now admins have permission to delete anything. It is all up to how you set things.