Q: Having looked at the tool converted code I think the best approach would be to "rewriting the code to use a .NET emulation of ADODB (this is compatible with what you have, but still requires some work)" because any other option would require significant re-engineering to make the application work. I wanted to run the FMStocks sample, however I couldn't find the SQL database in the zip file. I tried accessing the http://www.fmstocks.com/ website but it is not available. Wonder if you could send me the SQL script or data file by email.
A: Regarding "having looked at tool converted code": bear in mind that you are looking at a default conversion. gmStudio can produce other code based on the rules you provide including automating most of the "significant re-engineering required to make the application work". I know I mentioned this already, but most developers have difficulty grasping this concept because this type of flexibility has never been available in a software "converter". These developers believe if they must take whatever code the tool generates right out-of-the-box and finish it by hand. I admit it does take effort to learn how to setup rules and ADODB is a big API and it is a quite different from design patterns for other .NET data access techniques.
Having said this, the C# will be your system in the long term, long after the conversion. This is your decision to make. So, having said that:
I uploaded a copy of the database files: http://www.greatmigrations.com/pubs/stocks_data.zip (SQL 2008)
They can also be found here: http://www.microsoft.com/en-us/download/details.aspx?id=666
The Dec 2013 version DataLib and unit tests are here: MigrationSupport.DataLib.zip
See also Support Statement: Stub Replacement