yes, using underscores in the column names causes the parameters to be created in a way that Dreamweaver will not interpret. The pages should run fine in the browser, but testing the record sets in Dreamweaver will cause errors.
For the undefined offset issue, what data types are you using in you database?
We have seen this issue happen a few times, but have not been able to pinpoint the cause. Editing the inert and update record behaviors to set the data type will corect the issue.