I want to be able to create a database project in Visual Studio 2008 and have it contain a reference to our Informix 11.5 database.

I've been trying for 8 hours or so to install all manner of client SDKs, play with registry settings, uninstall/reinstall .NET Frameworks and .NET Framework SDKs, along with Windows SDKs.

I cannot for the life of me get anything to show up in the
tools->connect to database...->Data Source Change...button aside from the microsoft drivers.

My only option is to use the ODBC Data Source option with .NET Framework Data Provider for ODBC. If I do this, I cannot run half my scripts because the ODBC driver, evidently times out if something is not returned in 30 seconds.

I've read pages on the net where others are describing a driver option for Informix/DB2, etc.

I made sure everything was checked when I installed the client SDK.
What am I missing?

Keep in mind, I do not want to write .NET code. I want to create a database project and run SQL scripts while viewing the tables and contents.

The CommandTimeout needs to be increased in the VS application.
The following link will show an example:
Increasing query time-outs with TableAdapters - Smart Client Data - Site Home - MSDN Blogs

Informix ClientSDK uses the application timeout and for Visual Studio it is 30 seconds.

I hope this helps.

There is no application.