State of licence issued 'shouldn't' make a difference.
Requirements to simply renew the 5 year CPL licence is to have a valid Class 1 medical and a type or class rating that hasn't expired by more than 5 years. Your CPL skill test would/should have renewed either your SEP or MEP rating, which are valid for 2 years or 1 year respectively, therefore neither of these will have expired by more than 5 years.
Simply get your paperwork sent in with a valid medical and a fee (i guess they charge in Belgium) and your licence will be renewed.
Obviously next time around you'll have needed to have renewed a rating since the initial CPL skill test rating, as that will be well over 5 years since expiry.