If you are only swapping out partitions, and then splitting - i.e. not swapping in the data (and indexes!) to the new partition then the indexes for that partition will...
I build an empty table and create the relevant indexes on that filegroup and switch it into the newly created partition (after splitting). Even though I don't switch any data...
If you need the guid generated outside of SQL Server then you will have to create a sequential guid yourself. In your case this is because you need to insert...