I'm using localwp on Windows. My source code is in one directory, and then I copy it to the localwp directory where it's accessed by WordPress, PHP etc.
Visual Studio stops correctly on the breakpoints, but opens the copy of the file (in the localwp directory) rather than the source directory.
I've set up manual path mapping, and this seems to be confirmed in the Debug output window.
Is there anything else I should be doing?