Modules & VBA :: Record Locking Multi-users Over Network Split Database / Access 2007

I have designed a database which I intend to split for multi-users to access from one front end icon on a shared folder at work. I have designed a form bound to cmr record table and on it a subform to another table where cmrs activities will be saved. The form has buttons to and blank controls.

User can create a new activity entry by typing into the blank controls and pressing the save button which saves to the activity table. the edit button extracts a selected records details (selected on the subform) from the activity table and populates the blank field for a user to edit and then hit save to save changes. The delete button deletes a selected record from the activity table. I intend to have multi-users either accessing, viewing and a possibly editing the same customer at the same time. The simultaneous viewing is essential but the simultaneous editing, though not desired is inevitably going to occur.

What I would like to know is:

1. Can you lock an individual record in a table or does the whole table have to be locked. E.g If Colleague 1 is editing Cmr A's record in Table1 can he lock it so Colleague 2 can view and edit Cmr B's record in Table1

2.Can Colleague 1 access/read Cmr A's record in Table1 to retrieve details toe the form controls if Colleague 2 is viewing or editing Cmr A's record in Table1

3. If record lock is possible, how can I initiate it in my example code below.Edit activity record Code

Code:
Private Sub Edit_A_Click()
'Get Data to text box control
With Me.R_P_Data_P_Subfrm.Form
Me.txtrID = !rID
Me.txtrID.Tag = !rID
Me.txtrefNo = !refNo
Me.cmbrpc = !rPC

[code]....