You could manually trick it by going to your appdata path and creating new dir for TDP 4.3 and copy over the files from TDP version you want to migrate to.
IE: Copy files from here
C:\Users\%yourprofile%\AppData\Roaming\Quest SoftwareToad Data Point 4.2
To
C:\Users\%yourprofile%\AppData\Roaming\Quest SoftwareToad Data Point 4.3