AX2012 Feature pack year end process

When the feature pack is installed, it defaults the licence key for public sector. Didn’t knoiw this at first and have gone live with this.

We now are trying to process the year end closing and opening balances, and have completed the closing sheet as normal. But when I come to process the “Opening transactions” form, I am presented with the message of :

“Posting definitions are required for year end general ledger close. Select the ‘Use posting definitions’ checkbox on General ledger parameters.”

Now, I’m a little nervious with just ticking this checkbox as I’m unsure what this could do to my normal sales and purchase postings, has anyone else come across this issue ? If I switch this on could I end up with AX2012 ignoring my normal posting profile settings and using this instead ?

We do not want to use the posting definitions if we can help it and would be grateful if anyone could advice me on how we should deal with this.

Many thanks