
Your configuration folder may have become corrupted. You can rename the configuration folder to have Dreamweaver recreate it. Close Dreamweaver and go to:
WinXP
-DW8
--C:\\Documents and Settings\\<Your User Name>\\Application Data\\Macromedia\\Dreamweaver 8
-DWCS3
--C:\\Documents and Settings\\<Your User Name>\\Application Data\\Adobe\\Dreamweaver 9
-DWCS4
--C:\\Documents and Settings\\<Your User Name>\\Application Data\\Adobe\\Dreamweaver CS4\\en_US
Win Vista
-DW8
--C:\\Users\\<Your User Name>\\AppData\\Roaming\\Macromedia\\Dreamweaver 8
-DWCS3
This will disable all the extensions in your extension manager. After doing this, can you try installing DataAssist on its own and try the wizard again?

Before I go off and create hours and hours of work with a few simple clicks:
Are you saying by deleting that folder, that I will have to either re-install or re-enable all of my DreamWeaver extensions?
And, are you suggesting that with all other extensions removed?? or disabled?? that I try installing DataAssist all by itself to see if it works?
BTW, I think I own every just about every WA extension.