1. The creditor (or a debt collector acting for them) can pursue more than one method of enforcement, so they can try to get the money from you as well as having the charge.
2. In some circumstances interest can be added to the debt after the Court judgement (CCJ) has been made, at an exorbitant rate of 8% pa. I think the debt has to be above £5K for this to apply, & there may have to be other conditions complied with.
3. You need to find out who the creditor now is - it might be whoever the liquidator is for the original firm, or they may have sold the debt on.
4. Don't ignore this. If you do, they could go to Court and ask for an order for sale of your house to recover their money.