If you upgrade with Live Updates, you will never see the actual version number in the "Add/Remove Programs" section of the Control panel, because that will only tell which was the version of the last full installer you ran. To see 1.4 in that page, you need to use the full installer.
However, the difference will be just cosmetic, because the Addon Manager update will update GSX just the same.
We'll try to have the version number changing in the Add/Remove programs page too, because I understand it might cause some confusion.