Upgrade failed from 1.3.7 to 1.4

[FireHawk]

Hey all.
The other day i tried to upgrade as i am desparate for the "guest can checkout" to enable the google banner on my google adwords campaigns.

Followed the instructions to the tee (or at least i think i did).
After transfering my images etc, uploaded all the "new files" to my server (over writing existing files)
Went to the install page and clicked on the upgrade.
All seemed well, but at one point i noticed that it said version 1.4 already installed.
Clicked on continue and at the end it failed.

Had a look at my shop and there was only one big picture showing on a white screen. Started to pull hair out as i went in search of what to do next but couldn't find anything to help.
Resorted to deleting all the files on my host site and putting back my existing copy of them that i'd took before the upgrade.
Took some time to sort out as i didn't know how to restore the database. I'd got no products showing but got there in the end.

So, i still want to upgrade but i am scared that it will just do exactly the same and take me another 2 days to get back to my old version again.

Have i missed something obvious?
Would an expert be willing to help me upgrade?
I am quite a novice when it comes to myphp etc so some of the terms used go above my head and i have to go googling lol.

Any help or advise would be greatly appreciated.

[Billy]

Best advise would be wait for the new 1.4.1 release in a week or so... Lots of issues have been address!