Unable to select width and height using Gigapixel for Windows

Using Gigapixel on Windows 10 and I cannot change the width and height settings. When I drop a new file in it always shows as 4x in the row that displays the filename. If I try to enter a Width or Height instead of using the Scale feature, it simply changes back to the number of pixels that 4x would be.
When I do change the Scale the selected file never updates and always displays 4.00, nothing I do seems to change it. Also, the Input image size and Output image size are always showing 0px0px.

UPDATE: In case anyone else encounters this problem, I saved the JPG images from the web and for some reason, they showed up as 0px0px in Gigapixel. After resaving them from Photoshop they now show their correct size and I am able to resize them as expected.