First, this is something that we plan to overhaul in the future. We will most likely have different signatures for each update. This will allow you to install more than one version of SF at a time. We will also most likely change assembly names as well to ease this also. The major change will have to occur design-time so that more than one version can be used at a time. So this will have to support multiple versions of the BO Mapper, etc.
So, what we'd like to do is figure out a quick simple way to quickly upgrade/downgrade the design time DLLS and VS extensions, not just our referenced libraries in the projects but also the VS design time without going through full install/uninstall. Is this possible?
At present, if you just need to support multiple versions, you can have more than a single SF version in the GAC which will give you all of the capabilities to maintain each version as well as build and use type editors. The downside is that the SF BO Mapper could potentially cause a problem since this changes (even if minor) between some SF versions.
Also, if we can feasibly do this, would you recommend keeping versioned Strataframe databases or are the changes made to this database backward compatible.
If you are going to need to retain the ability to use the BO Mapper, etc. then yes, this is probably a good idea. Like I said, these are all issues that we intend to address long-term, but at present, you will have to take an approach like this.