For everyone that creates Virtual layers and know the pain that implies the fine tunning to support the complete feature set of the virtual versions of the applications, there is a new product which was designed to help you in this painful task.
SpyStudio is an Application tracer which shows and interprets calls, displaying the results in a structured way which is easy for any IT professional to understand. SpyStudio can understand the resources that an application uses, track down errors, detect malware and create application layers for virtualization.
SpyStudio has a trace comparison tool which is useful for identifying problems in virtualized environments. You can obtain two samples: the native version of the application and the virtual version which has the problems. Using the 'Compare traces' feature, you can see what is missing in the virtual environment. SpyStudio is the user-mode complement of Process Monitor.