Update a table

Experts,

I have a form frmLetterOfCredit_Cont that is built off of tblLetterOfCredit.
I also have a form frmLetterOfCreditAdd built off of tblLetterOfCredit.
What I need to do is update [region] that is contained on frmLetterOfCreditAdd without having to actually go to this form.  
[Region] is a combo box.

While on frmLetterOfCredit_Cont I enter in the "Country" from cboCountry on this frmLetterOfCredit_Cont and after I update this I want to be able to update this field named cboRegion [Region] on frmLetterOfCreditAdd

both forms are built off of tblLetterOfCredit.  

The reason I want to update cboRegion instead of actually going to the form is becuase the network is a little slow and I do not want to transfer this field to frmLetterOfCredit_Cont but let it remain on frmLetterOfCreditAdd.  

cboRegion on frmLetterOfCreditAdd rowsource:
SELECT tblRegion.ID, tblRegion.Region FROM tblRegion ORDER BY tblRegion.Region;

I guess I would need an unbound form with cboRegion on it and then once I select one of the options from the dropdown box then the [Region] field on tblLetterOfCredit would update with what I selected from this unbound field on a form called say frmRegionPopUp.

Maybe there is a much simpler way to do this.  I am open to suggestions of how I could update the value on the combo [Region]  under tblLetterOfCredit while on frmLetterOfCredit_Cont without having to actually go to that frmLetterOfCreditAdd where [Region] resides.  Keep in mind that the both forms contain tblLetterOfCredit and I could get a WriteConflict error.  

LetterOfCreditID is the link between the forms frmLetterOfCredit_Cont and frmLetterOfCreditAdd.

thank you.  Please ask questions if not clear.

I attempted to do this myself with an AfterUpdate on cboCountry but did encounter a write conflict error (but now I believe an UNBOUND form would be better than a bound form which is what the frmRegionPopUp was built off of (tblLetterOfCredit).

Private Sub cboCountry_AfterUpdate()

     If IsNull(Me.cboRegion) Then
        MsgBox "Enter the Region of Export on the LC Detail form (click LC No)", vbInformation
    '    DoCmd.OpenForm "frmRegionPopUp", , , "[LetterOfCreditID]=" & Me.ID, , acDialog
    'Me.Refresh ' have an issue with write conflict...removed docmd. 3/15/11 have tried refresh, requery, dirty...posted EE.
   
    End If
   
End Sub



Hope it makes sense.  Let me know if you have any ideas.