>>> The data displays fine when I run it directly in Crystal reports 10, but when I run it from my VB.nET windows forms application, nothing shows up.
Are both of them hitting the same database? Did you make sure that when running in Crystal you are really hitting the database and not just looking at saved data (File -> Save Data With Report) option?
When you changed the import query did you change the select command for a VB.Net DataAdapter? If so, did you remember to regenerate the associated DataSet(s)? I assume you had this working before so you're calling the DataAdapter's fill method?