Migrating Biztalk 2000 and 2002 versions

4 years back I worked on a Biztalk migration from 00 to 04 . I am also currently in the processing for upgrading biztalk 02 to Biztalk R2 version.I had to migrate the following which were the tougher ones
AIC, Maps
We had maps with Vbscript as that language seemed to be the most commonly used one back in 2000 and 2002.Like you said the migration wizard dosent help at all.Here is what I did.Hope it helps
1.For each of the specification document[DTD] ,you will need to convert them to an XSD or recreate if necessary for all the DTD's thats are hard to convert. 2.Visual Studio has an option to convert the DTD to an XSD either by opening the DTD,Menu-->>XML-->Create Schema or the other option is use the Schema generation wizard to create a XSD out of a DTD. 3.Get the xsl from the Biztalk 02 map.You can do this by compiling the map and the xsl is outputed. 4.Once you have successfully converted your source and destination schemas,create a new map and assign the new schemas as source and destination. 5.The xsl that you got in step 3 should be set in the custom xslt property. 6.When you test the map,you will notice that vb script is no longer supported.You will have to manually convert vb script to VB.net code.The best way i found for this was to take the vb script code and converted to code using a wizard and then manually corrected the output for it to work. 7.Once you have the new xsl,yours map should work without any issue. 8.The disadvantage of this process is that you cant see any functoids from the previous maps,but you will be able to add new functoids on the new map.
The remaining solution should be straight forward.If you have an AIC,you can convert the AIC to a custom adapter or re-write the AIC as a .net component or webservice.
I understand this could be a pain doing this for 3000 to 4000 maps.But I don't see any another solution from my point.If anyone else has a better approach,please advice.