Having issue using TMVL in script logic

Question

Hello experts,
We need to replicate the behaviour of the copy opening Bal through script logic.
Below is my code:
where user selects only entity when he runs package,time is derived from property.
// Year from version property
*SELECT(%YEAR%,"[YEAR]","Z_VERSION","[ID]='BUD'")
// Months
*SELECT(%MONTHS%,"[ID]","Z_TIME","[YEAR]=%YEAR% AND LEVEL='MONTH'")
*XDIM_MEMBERSET Z_TIME=%MONTHS%   (for ex:My first month is 2009.jan(ope month)
   *WHEN ACCT
           *IS CHC          
        *REC(FACTOR=1, ACCT="CHC",Z_TIME=TMVL(1,%MONTHS%))  ( for ex:2009.feb,nxt month)
    *ENDWHEN
When i run the above logic in debugger TMVL doesn't show next month.
If i hardcode time in my xdimmemberset to (*XDIM_MEMBERSET Z_TIME=2009.JAN) and change my TMVL in my REC statement to TMVL(1,2009.JAN)).Logic works fine.
Please tell me how can we pass dynamic variables to TMVL.
*REC(FACTOR=1, ACCT="CHC",Z_TIME=TMVL(1,%MONTHS%))
Thanks

Answer 1

copying closing bal of prev month to nxt month.
for ex:
Account     jan 2009    Feb 2009    Mar 2009
HC_PLAN     10.00      11.00      21.00
CHC          10.00      11.00        11
TI                     1.00                      1.00
TO                      2.00      1.00          2.00
AP                      3.00                       3.00
RT                       4.00                        4.00
My logic needs to copy values from HC_PLAN (parent) to CHC. I have written ope_bal logic in MS version.
In NW i cannot use next (i am using TMVL),calc_dummy_org,calc_each_period.
Please tell me how can i get values from a parent (HC_PLAN).
Is Calculate_Difference is supported in BPC7.5NW?
Below is my updated code
*SELECT(%Year%,"[YEAR]","Z_Version","[ID]='ACTUAL'")
*SELECT(%Months%,"[ID]","Z_Time","[YEAR]=%Year% AND [LEVEL] = 'MONTH'")
*XDIM_MEMBERSET Z_TIME=%Months%
*XDIM_MEMBERSET EB_ACCT = CHC,TI,TO,AP,RT
*WHEN EB_ACCT
           *IS CHC,TI,TO,AP,RT         
                  *FOR %MonthCopy% = %Months%
                       *REC(FACTOR=1,EB_ACCT="CHC",Z_TIME=TMVL(1,%MonthCopy%))
                    *NEXT
             *ENDWHEN