[AccessD] Most common problems/situations

I'm trying to gather a list of the most common problems and situations
faced by an Access developer (strictly referring to design/coding/form
types/control types/classes, etc., and leaving aside problems such as
time-and-billing, getting paid in a timely fashion, how to factor into your
billing rate the depreciation on your hardware and software investments,
etc.).

The initial ones that come to mind are:
- Input masks
- Master/Detail forms (could be nested, as in Customers/Orders/OrderDetails)
- Combo boxes (also involves Cascading Combos and NotInList behaviour)
- List boxes (also involves NotInList behaviour)
- Linked forms (a pair of forms; navigation on either causes navigation on
the other)
- Office Integration (links to Excel, Word, Outlook,etc.)
- Custom Nav buttons (assuming you don't like those built-in)
- On-the-fly creation of new forms/dialogs/reports
- Search and Filter facilities
- Reports scoped to either the current row, or criteria
- API calls
- Export current record/report to PDF and email same
- (Advanced) Creation of custom classes, most commonly custom controls

These are the common problems I have commonly faced and addressed. Do you
have others to add to this list? Eagerly seeking addition to this list.

-- 
Arthur