Check that your image filenames use only web-safe characters (uppercase and lowercase letters, decimal digits, hyphen, period, underscore, and tilde) and not other characters such as commas or apostrophes.

Also, if only 44 images load in svBuilder-Pro, check the 45th <image> entry in the gallery's XML file. Open the 'gallery.xml' file in a plain text editor and make sure that the 45th <image> entry corresponds to a file in the 'images' folder.

If this does not help, then try creating a new test gallery in svBuilder-Pro and add the images to the gallery in small batches to see if you can find a corrupt image which may be causing the problem.