Maharashtra sales tax return

Dear All,

 I have filed VAT/CST return in JUNE 12 for Maharashtra but while calculating the TAX i have merged both VAT & CST ( for eg.Rs.5000+Rs.10000) in VAT , due to which there was no CST payment , and

now i have to reviesd the return , but my question is that whether i have to make a separate payment( with interest ) for CST ? ( i.e. for Rs.10000)

Also , at present  i have an excess amount with me of say Rs.35000 , is it possible to adjust the same ??