Desperate For Help

I have uploaded a database that I am working on it, and would appreciate it if someone could look at it and help me out, as I have gone through the forum trying to resolve my issue. There has been some topics on combo boxes and subforms and some of the posts only help me partly to my requirement.

When a user hits the button 'Enter Rate for Supplier' (which is to be double clicked, all buttons on the forms are double clicked) on the form 'Main form' a form 'Rates' comes up with a combo box and a subform. What I want then to happen is that a user selects a 'supplier' in the combo box, and then goes to the subform and selects the class and enters the rate. Note, the supplier names appearing in the combo box are entered through the form 'Enter Supplier Details' which is launched after the button 'Enter Supplier Details' on the main form is double clicked. Details entered through this form populates the table 'Supplier Details'. After entering the class and rate for that supplier in the subform the table 'Rates' is populated.

What I want to see is that after when they save and close the form, they can go back to the 'Enter Rate for Supplier' form select the supplier from the combo box and all the information that was entered previously in the subform for that supplier appears in the subform again. Then the user can produce more records by select more classes and enter rates.

So based on what I have stated above can someone please help me in making this happen. If you can also summarize how you did it, when you reply I would really appreciate it, in where your explanation could also benefit others like myself who is only an immediate. Also by all means you may keep the solution in the database for self education purposes.

Thanks so much for your help
Greg