The installer needs to be ran for each user to copy and create all the special files in each user's localdata directory, but you state you have done that...right?
Could you also check at the top of the install.log whether the userdirectory is the correct one? :
Remove old SCITE_USERHOME
Add SCITE_USERHOME to registry
Tell Windows to Update Enviroment
Output folder: C:\Users\UserB\AppData\Local\AutoIt v3\SciTE
!!!! SciTE FULL
Copy to C:\Users\UserB\AppData\Local\AutoIt v3\SciTE\abbrev.save.properties
Jos