First thing I do is make a new empty user data folder with a meaningful name and in the location I desire, such as "TS22 Beta Content." I then download a fresh 19/22 app from my MyTrains Downloads. I install that into a separate folder named something like "TS22 Beta" - Once installed I run any patches (updates) needed to bring it up to the beta version desired (I keep a list of every beta release and it's version number with a link to it's announcement on the forum.)
The new install will have created it's own user data folder so now it's time to point the new install to the new "TS22 Beta Content" folder. Point the installed app to your content folder and restart. Verify that path to content folder is correct. (Optionally, copy existing content folder from old install and give it the new name.) Personally, I redownload DLC and DLS content each time I make a new install. I also then install my own and 3rd party cdp's and such. I can say that by installing content "fresh" again I seem to not have a lot of the issues reported in the forums. Tony also suggests that it's best to install content again rather than copy/move/rename existing content folders. But that's a personal call... I also have the advantage of having rock solid and fast download speeds (needed for my work at home.)
Hope this helps. Counting Tane, I currently have 5 separate installs. I put the apps on my C:drive (SSD) and user content on my D:drive (SSD). That works well.
