Using 10.6.8 OS on my Mac, I’ll no doubt download new via zip, since I saw a warning against .dmg download. I’m wondering if I need to purge my Mac of older versions of Audacity. I currently have 2.0.3 installed. Is 2.0.6 a stand alone? Or does it augment and build-on 2.0.3? Or do I leave older versions on my Mac and just ignore them, and use 2.0.6. I just want to make sure there are no conflicts with older versions, and how to avoid… or purge them correctly first, before doing install.
Thanks for any help I might receive clearing this issue up. 
I saw a warning against .dmg download.
Where?
Successive installs of Audacity are all self-contained. What they do is assume the preferences and settings of the one before. So if you had a particular operating environment you liked before, for the most part, it should survive the upgrade. The downside of that is if you screwed up your preferences, that will stick to you, too.
You can install more than one Audacity by installing a “Portable” version. Attached.
Install Audacity in its own separate folder different from the default one.
You still can’t run more than one Audacity, but you can pick the one you do run.
Koz
