Image Gallery with Slideshow is a full integrated Image Gallery and Slideshow plugin for WordPress
Ans. There is no limitation of uploading Images.
Ans. From Gallery listing page in admin click on the Gallery name, you can view the Images for that particular Gallery.
Ans.Yes, you can use, for that you have to set the "Root Path" option in "Gallery Settings".
Ans. Whether you're reporting a bug, requesting a new feature, or just wanting to make a comment, I will be happy to hear from you. The support forums can be found here.