How to upgrade the entire Bitnami Redmine stack?

Question

So I have a server, and I know the pieces of the stack. Like:

• I know how Apache works, how it's configured.
• How Redmine works, where it stores the files for itself.
• How to migrate from each app to a new version.

But the problem is... how do I update the entire stack?
There is a wiki entry on the Bitnami site, but I seriously doubt that would work.
See for yourself.

This is the worst part:

You should also copy any uploaded files and configuration files. It also could be necessary to run migration scripts to update the database. This depends on the application itself.

Now, the apps sure are located nice and tidy in the Bitnami folder, but it is still no easy job to watch each single application: where it goes, where it works from, etc.

Is it even possible to upgrade the entire stack?
I mean, Bitnami is not a new thing, it should work sane. But if you have to spend days to bump a whole stack... why do people even use it? (I did not install it, some other guy did.)