[Q] Should I delete CNMO first before installing

[stbens]

I currently have the original game installed via Steam. Should I uninstall it first before installing CMO or does the new installation simply update the old files? If I do have to delete the original game should I back up the extra scenarios I have installed?

[mavfin]

I wouldn't delete it. Unless you have low disk space, leave it. CMO will know from the CMANO install whether you have the DLC or not, etc.
Also, if you have a community scenario that won't load in CMO, you can load in CMANO, see what DB version, and copy it over if you need to.