I got my Artec e+Pro usb scanner to work under vista , this may work for the 48u.
Credit to nasirimran , and his post http://forums.driverguide.com/showthread.php?t=24259
for the below , I have just reworded some of it and can confirm it worked for my e+pro.
1) download the xp version driver of the above scanner onto the desktop.
2) right click the exe icon.
select properties , then compatibility and choose xp service pack 2.
Right click again and RUN as administrator
allow this program to run even though it has not been aproved by microsoft.
3) go to c:/windows/twain_32/ePlusPro/Scan32.exe
right click SCAN32.exe
select properties, then compatibility and choose XP service pack .
Right click again and RUN as administrator.
I actually created a shortcut to the desktop of scan32.exe.
Now everytime i click on this..........my artec e+pro scanner work absolutely fine.
The only problem is none of the shortcut butons work on the front of the scanner , but you can choose where to save the image to through the Twain program , then edit it it whatever programme you require.