You should consider updating to Sentry 4, which was a free update released in December:
If that does not work for you, then get in contact and provide some information so we can attempt to help you. Otherwise complaining about things not working and flitting between different products accomplishes nothing towards addons being improved! If there is something that needs to be fixed, we will be more than happy to look at it for you.
Sentry and ProGallery are a good match. You can setup ProGallery to read a CSV file or images from the Sentry media directory. Or combine ProGallery with the free Droplet, stack, if you want an unbelievably simple way for your client to upload new images to a web gallery, with drag-and-drop ease. Simple descriptions and prices can be abstracted from the image file names.