Just to make sure we're on the same page. is this the way you installed PowerGallery?
- Create folder on server for PowerGallery
- Change permissions to 777
- Upload PowerGallery files to new folder
- Run installation wizard through browser
You might also want to check for charecters in your password that could cause trouble. I had one with a * as the first character that worked fine on one Linux server but not on another. Don't forget that Linux servers are case sensitive whereas Windows servers are not.