The old one is, iirc, a clone of the PCOL (Possession Claims Online) system - another MoJ project centred around small claims.
PCOL dates from 2006 (I should know, I helped work on it, mostly performance testing using CompuWare to locate & iron out horrible Hibernate-on-Oracle issues...)
All of this was delivered by EDS, completely pre-dates the GDS stuff and shouldn't be considered anything to do with it. :)
Or the old one? https://www.moneyclaim.gov.uk/web/mcol/welcome