I have updated the broker-core module to support an "interactive" mode, in which the server is paused at the start of each activation cycle. Given the --interactive option on the command line, the broker sends a pause-request before calling the activate() methods, and then sends a pause-release message after all the service modules have returned from the activate() calls. This means, for example, that you can put breakpoints in your broker code and get the server to wait while you examine the state of your code. For this to work, you have to add a line to your server config telling it to accept broker pause requests; the default is to ignore them.
I hesitate to deploy this change until at least one other person has tested it. To try it, you will need to check out the Rboker branch and do a local install of broker-core, and re-build your broker. Then you need to specify the --interactive command-line arg when you run the broker, and you need to add the line