First I want to state that I am relatively new to Sql 2005 and schemas so I still think in terms of owners, but I think I can give you a good idea as to why you are seeing the behavior.

In the sp the sp is going to look for objects with the same owner as the sp, unless you qualify the name with the schema/owner. But when creating objects it will use the UserName unless the user is a dbo and then will create the object in dbo. So your sp is looking for dbo.tempo and not finding it. Similarly if you have Abrin3.Table referenced in a dbo.sp and the user does not have rights to the Abrin3 schema or direct rights on Abrin3.table then the sp will fail.

It is working with dynamic sql because dynamic sql executes in a different context then the stored procedure it is executed from, no longer in dbo.

Hope this helps, and that if I am in error someone else clears is up.