When I upgrade I move the Backup folder, TCPPrefs.ini, TCPShortcuts.ini, StdDim.ini (custom standards), files in the com.imsi.turbocadmacpro10EST folder to the desktop. In the symbols folder, I move the User folder (custom symbols) to the Desktop. In the PhotoRender folder, I move the Textures and Materials folders to the Desktop, these are custom texture and materials I have added through the "Render Library" palette.
Right click on the TCP icon and show package contents, drill down to "Resources" folder and move the BOM folder, if you have custom BOMs, Templates folder if you have custom templates. I don't recommend removing and replacing the Texture folder because IMSI may have added some new stuff here, instead keep copies of your custom images and textures in a seperate folder and copy them into the texture folder. In the "Environ" folder, CADD.LIN and Materials.ini are moved to the desktop if you have custom line types or materials (under Verify menu).
After the upgrade move everything back to where they came from replacing the existing default files.