Hi
answer for 1st question
For using .NET assembly in BizTalk project , you need to first add it in reference section , then you need to create a variable which is of type is class used in that assembly (This is creating object of class , normally we create in any language) , now use this varible in your expression shape to access methods of that class ……
But the most important thing is before using .NET assembly , you need to add few line in AssemblyInfo file these are
[assembly: ComVisible(false)]
false)]
[assembly: CLSCompliant(true)]
[assembly: EnvironmentPermission(SecurityAction.RequestMinimum,Read="USERNAME")]
and provide strong name key loaction in same AssemblyInfo file
Also add [Serializable] tag just above the class declaration
Sudershan