I’m testing Resolve 14 on another PC while the main one completes a big project on 12.5. The simple answer is no as David says as the databases are not backward compatible. Once you make a project file in 14 it can’t be read in earlier versions.
The 14 install effectively overwrites 12 as well. You can do the dual boot/ partition way. Or separate machines like I am doing. 14 is certainly impressive. Still beta so the Fairlight functionality is not fully implemented but this version will change a lot of perceptions about performance and editing features. And for all my video friends, they can start to get an idea about audio clip stacking and proper bus & multi mix architecture which is something I have banged on about for years.
If you install R14 in a system with R12 installed, R12 gets overwritten. Workaround is to Rename the R12 folder in Applications to DaVinci Resolve 12.5.6 or something other than just DaVinci Resolve. Now, Resolve 14 gets installed in a new folder called DaVinci Resolve.
However, if you open an existing project in R14, then it will never open in R12 again. Also, The Red decoder won’t work in R12 and you’ll get a warning to this effect.
What you could do, is to temporarily move the DaVinci Resolve (containing R12) to another place, install R14, but don’t run it, then move this R14 folder elsewhere. Run the uninstaller and uninstall R14. Then reinstall R12.
Now on, run R12 from the Applications folder, but run R14 from its new location only.
Even with workaround, if you open an existing project in R14, then it will never open in R12 again.
FCP Editor, Edit systems consultant