Yes NorthNone, the wizard can do that. I'm a person that doesn't like the wizard so I do all forms etc manually

Gives me better control of everything.
Commanderrico: You don't base your forms on a query/view? I always do. So then I'd advise you to create 2 queries/views and check that each one displays some data before building forms.
Cause I think this also can be caused by a wrong JOIN between you'r two tables, hence the form not showing up. Just try it, make a form that is based on a input value of ID. Then send the ID = -1 (for example, any ID that doesn't exist in the table would do). And see what happens.
Have you tried changing you'r tables relations to a LEFT or RIGHT join? (INNER JOIN) is default in MS Access. That could might help you do the trick. You can do it Tools-View Relations, rightclick a relationship and select propeteries. Select JOIN TYPE.
If you want to see what this does, create a simple query/view and then view the SQL code. The default database would have INNER JOINS, but change it and the SQL code would show you LEFT/RIGHT JOINS.