Hi Sam,
Sorry for the delay caused.
We are unable to reproduce the issue 'SampleBrowser_2010 project not compiled in windows 7 with wp sdk 7.1".
Please uninstall the current build and reinstall the build again and check the Windows Phone SampleBrowser project for compilation.
If the issue still persists, please find the location were WindowsPhone 7 assemblies has been installed.
Path : C:\Program Files (x86)\Syncfusion\Essential Studio\11.2.0.25\Assemblies\Windows Phone\7.1.
Please refer the assemblies from this path and compile the 'SampleBrowser_2010' project and let us know if the issue still persists.
Please let us know if you have any queries.
Regards,
Ranjith.S