No, from your error ( "Can't convert Unicode to Non-unicode data type".) your data is not varchar/non-Unicode, but it is the double wide nvarchar/Unicode.  Which is why I recommended...

Didn't know that off the top of my head, but 

https://docs.microsoft.com/en-us/sql/sql-server/maximum-capacity-specifications-for-sql-server 

explains it quite clearly.

Good question,
Rob

Not exactly sure what your (homework?) question is?  Show records that have NULL or 'Periodic' in the type field?
What have you tried?

Take a look at ISNULL()...

Glad you figured it out.  As you noticed, you need a tablix or a list to show multiple records.  If you just put a textbox, it'll only show the value...

Kind of a klugey idea, but what if you wrote to a table that uses nvarchar() (or Unicode aware) fields.  Then SELECT from the table, and write to your Excel...

What happens when you take the TOP 10000000 query from your OLE_DB source and just run it in SSMS?  Is tempdb fine in that scenario?  What if you insert same...