I just got back to the office and was looking over this thread to make sure all of your points were answered.
The PA-20S/PA-65 IS the main Pennsylvania partnership return. If you aren't signing and e-filing as a paid provider/ERO and she is mailing it in, at a minimum the filing will require:
Form PA-20S/PA-65
PA Schedules RK-1s for each resident partner and NRK-1 for each nonresident partner. Like the federal, copies of these schedules are to be provided to each partner for use in preparing the individual PA return.
PA-65 Schedule M - Reconciliation of Federal Income/Loss to PA Income/Loss
Any other schedules that the PA20S/PA-65 line items requires, depending on activities for the year
A complete copy of Federal 1065 and all of its attachments including the K-1s and 7004, if one was filed.
Sch M has its own set of instructions. This form "classifies" the income for PA purposes and then after that has sections for PA adjustments for items where rules differ from the Federal. Just a couple of examples that many businesses have that differ for PA are bonus depreciation, meals & entertainment, gain on sale of an asset....
I'd suggest more closely reviewing the instructions for the PA20S/PA-65 form, especially beginning on page 5 under "What to File" and on page 7 for detailed instructions for "Assembling ..." that includes the order of attachments since this will be mailed in.
You are probably familiar with the PA rule differences from the federal, especially regarding depreciation since you handled the B&B on their personal return too. Wasn't that a PA property too? If you aren't and need an additional resource, you could start with the comprehensive PA PIT Guide for Pass-Thru Entities that has the rules for depreciation, when MACRS can be used and under which rules, bonus depreciation, and sec 179 rules for PA purposes.
Have I mentioned lately that I dislike PA returns?