Below are some known issues with the MIX drop.
Multiple "Add Service References" from VS Express 2010 IDE, causes the ClientConfig file generated to be overwritten.
No "Add Service Reference" support in VS Pro 2010
Calling Assembly.Load(string) causes a crash in the native runtime
IsolatedStorageFileStream constructor throws IsolatedStorageException when Filemode.Append is passed and no FileAccess value is passed
Accessing Non-English (international) services throws an exception at runtime
IsolatedStorageSettings doesnt save the settings on app exit
Using variant type generic parameters results in TypeLoadException