JustTrace should be able to handle this scenario. The limitation is that your VB app must load the managed dll in the first 30 seconds after it starts. Otherwise our code decides that there is a problem starting the profiled application and stops the profiling session.
If you are unable to make it work, please open a support ticked with us.
Check out the Telerik Platform - the only platform that combines a rich set of UI tools with powerful cloud services to develop web, hybrid and native mobile apps.