Version Control and new VMs

Hi,


I started to play recently with Squeak and Smalltalk. My impression is
the Squeak and the Seaside Framework are moving targets, very exciting
pieces of code, but if I start a project this week, in the next week
will be available a new VM, or a new image, a new Seaside version,
etc...

Very good, because it means a very productive and creative community.
But if I have a project, and want to migrate to a new image version?
or to a new Seaside version? What is the right/easy way of doing this?
Change sets?

Maybe my question is how to do version control and manage conflicts?
How to migrate to new images?

Thanks,
Fabio