Thanks for the quick response.
The assumption that the other web site (the current one on the server) is under my control would be wrong. Although a simple example, we have lots of web sites running on a given server and we can never do anything to one site that would break the other sites.
In this particular instance, yes I could migrate the current app from vs2012 to vs2013 and use the 09 Crystal. But looking forward, each site has to exist autonomously.