In the test run configuration dialog, in the Code Coverage section, it is possible to select which assemblies get instrumented. There is also a "Re-sign..." button that, when clicked, brings up a "Binaries to re-sign" dialog which seemingly allows only a single key file to be used for signing the assemblies. This seems to be a problem, if the assemblies were signed using different key files. Or am I misinterpreting the UI here? Another problem with the "Binaries to re-sign" dialog is that it only seems to list the directories of the assemblies, and not names of the assemblies themselves.