Hello,
I'm working on a transaction setup where I send transaction, and the server responds with expected results. When I'm running the debugger, I can step throught the code to the end of my request php page, but when the server responds, it runs the desired page, but I cannot set breakpoints in the file.
Is there a way to do this?

you may want to see "HOW TO RUN DEBUG SESSION" topic in the FAQ. Also please look for DebugBreak() function call.