After rereading your post, you say that you have more then one CB but you do not say what sheet(s) they are on. I also see that you are referencing one list, A1:A5, on Sheet2.
Assuming that all ComboBoxes are on Sheet1 and all Lists are on Sheet2:
1. Open your Name Manager window by pressing Ctrl and F3.
2. Click on New
3. In the Name: box, type in
Size
4. In the Refers to: box, place this formula
=MATCH(9.99999999999999E+307,Sheet2!$A:$A)-ROW(Sheet2!$A$1)+1
5. Click OK
6. Click New again
7. In the Name: box, type in a name for your range (I used Data)
8. In the Refers to: box, place this formula
=OFFSET(Sheet2!$A$1,0,0,Size)
9. Click OK
The above will take care of the first Named Range and Combo Box1.
For the second Range and ComboBox repeat the above but you will have to give a different name for each. (i.e. Size2 and Data2). You will also have to adjust the column and row references in the formulas.
Also in the Sheet Module the code will look like this for two ComboBoxes
Code:
Sub WorkSheet_Activate()
Worksheets(1).OLEObjects("ComboBox1").ListFillRange = "Data"
ComboBox1.ListIndex = 0
Worksheets(1).OLEObjects("ComboBox2").ListFillRange = "Data2"
ComboBox2.ListIndex = 0
End Sub