When we define the intercompany rules and define Debit and Credit account(ON AGIS Window),in your example you created a Three segments account(Company/BSV.Account.Department)
where as my COA(new created) has got Four segments ( Company/BSV,Account.Department.Intercompany).
What do you suggest? Or shall I choose All Other-All Other option?

Perhaps you are talking about "intracompany" (not intercompany).

In the rules you specify which GL accounts should system use on the debit side and which one to use on the credit side, in order to balance the trade that is taking place between two balancing segment values (companies within one legal entity). This dicision is irrespective of how many segments you have in your COA or whether you have intercompany segment or not.

For example, lets say I have created one intracompany account in my system: INTERCOMPANY and I have three companies represented by balancing segment values: 01,02,03. I want this account to be used for intercompany balancing whenever any company traders with any other company.
I will define my rules as:
ALL OTHER - ALL OTHER, DR ACC: INTERCOMPANY, CR ACC: INTERCOMPANY

Lets say I have created 3 intracompany accounts in my system: INTERCOMPANY1, INTERCOMPANY2, and INTERCOMPANY 3. I want INTERCOMPANY 1 account to be used whenever company 01 trades with company 02, INTERCOMPANY 2 account to be used whenever company 02 trades with company 03, and INTERCOMPANY 3 account to be used whenever company 03 trades with company 01.
I will define my rules as:
02 - 01, DR ACC: INTERCOMPANY1, CR ACC: INTERCOMPANY1
03 - 02, DR ACC: INTERCOMPANY2, CR ACC: INTERCOMPANY2
01 - 03, DR ACC: INTERCOMPANY3, CR ACC: INTERCOMPANY3

You can specify different accounts on debit and credit sides as well.