I would post the balance in the bank account (1200) by highlighting that account, going to Details , going to Balance OB. The other side of the entry will go to 9998 Suspense Account. When you get the rest of the TB (and you need it!) by posting the entries to the various balance sheet accounts using the Balance OB function, it should clear the suspense account. You will need the TB for the rest of the figures (like debtors and creditors which will need to have any outstanding invoices posted individually using the OB button to match up to the figures on the TB.
I hope this helps!