Chuck:
Everything in your Problem List on the Summary Sheet should be accessible from that drop-down menu. Did you scroll down? You only have to pick out the ones you want to address.
If the patient has new problems that aren't on your old problem list, choose them with the ICD-9 search tool. They will be automatically added to your Problem List under the Summary tab, and they will also appear in the "Assessment" field. Copy, paste, and continue as above.
If I am misunderstanding your problem, please let me know.