Importing into Access
The raw csv format tables can be imported as "Text File" (External Data tab).
Demographics
Load PATIENT_ID as text, since Long Integer is too short, and double has problems (at least 10 selected PATIENT_ID's would not match when used to select using the same ID).
Encounters:
set PAT_ENC_CSN_ID to double
For Date, change name to DATE, and make sure it's month/day/year format ("Advanced" button at bottom-left.)