OK, you've downloaded and installed Dabo. Now how do you keep up to date with the constant improvements and bug fixes?
There are two main strategies for updating; which one you use will depend on a) how active you are in developing Dabo, and b) how willing you are to occasionally have Dabo break on you.
To get the most current, bleeding-edge version of Dabo, you should check out a copy from the Subversion repository, and regularly run svn up to update your Dabo installation. The benefit of this is you get improvements and fixes as soon as they're available; the downside is that these revisions can occasionally result in your Dabo installation being in an unstable state. These broken versions are always quickly reported and fixed, but if you're in the middle of developing a project, such instability can make development difficult.
The other option is to use Web Update, our system for pushing updates out when we know that any recent changes are stable enough that they won't cause your app to crash or anything like that. Sure, there may still be some bugs, but they were probably there before the update. You can set Web Update to automatically check for updates every time a Dabo app starts, once a day/week/month, or to only check when you tell it to. In any event, your code will never be updated without first asking you. If you choose to update, it should only take a few seconds, and the next time you start up Dabo, you'll have the latest stable code running.
If you are helping to develop code for Dabo, you should definitely be on the latest revision from Subversion. Everyone else should probably be using Web Update.
One thing to keep in mind is that these two options are mutually exclusive. If Dabo sees that it is under Subversion version control, it will disable Web Update. The reason for this is that updating a version-controlled distribution from anything other than the version control software will leave the files in an undefined state, and will cause lots of problems. So pick one method and use that. You can always switch update methods by deleting Dabo and re-installing using the other method.