I downloaded the RM9 update today and was about to install. But, did want to ask; is the company advocating completely uninstalling RM8 before moving on to the latest version? I seem to remember that in the past. But, perhaps it was for different reasons.
You can install both version at the same time. Many of us have at least 7, 8, and 9 installed. The one thing you need to do is copy your RM8 database file to a new place BEFORE opening it in RM9 because there is a conversion that happens and if for some reason you need to go back to RM8, you will have to restore a backup. I am on a Windows machine but I have separate folders for RM4, RM7, RM8 and RM9 datafiles.
If it is a RM7 database, it will import into either RM8 or RM9 and the RM7 database will remain on your system unharmed after the import. It is just the 8->9 conversion that could cause fits. I still would strongly suggest maintaining separate folders for the various version’s datafiles.