If the only difference between a working gallery and a blank page is the method by which your mobile device's browser receives the gallery files, then perhaps your 3G connection is taking much longer to download the files from the web server.
Try testing the speed of your 3G connection vs your WiFi. If found to be much slower, does the gallery show up after some time has elapsed?

The gallery files have not changed and you experience this with all SimpleViewer galleries.
The only variable in the equation is your connection (3G vs WiFi) and you do not experience any errors using WiFi.
It sounds like you may be experiencing time-out errors with your 3G connection before the JavaScript files have been fully read. Are the 2 error messages you get always the same when viewing different galleries (of the same version of SimpleViewer)? What exactly are the error messages?

Try viewing a much simpler gallery (than the 'Forest' gallery as depicted in your screenshots) to see if this is displayed using your 3G connection.
Here is a simple 2-image SimpleViewer-Standard gallery to try.
[Gallery removed.]

I do not know the reason for the problem though a slow connection could certainly account for timeouts.
Do you experience blank pages when accessing any other web sites via 3G?
What happens when you try to access a page which has other content as well as a SimpleViewer gallery, such as this WordPress page containing a SimpleViewer-Standard gallery?