The mobile suits racing from Earth to help Amuro in the end are RGM-86R GM III's, which were originally featured in Mobile Suit Gundam ZZ.
The mobile suit that Amuro pilots in the beginning and which Kayra later pilots, the RGZ-91 ReGZ ("Refined Gundam Zeta"), is a derivative of MSZ-006 Zeta Gundam from Mobile Suit Zeta Gundam and Mobile Suit Gundam ZZ.
The bright, multicolored Hi-Zack Mobile Suit that makes its appearance inside the colony is called a 'Hobby Hi-Zack' This is a civilian use version of the RMS-106 Hi-Zack used by the Earth Federation and Titans during Mobile Suit Zeta Gundam. During Mobile Suit Gundam ZZ, the Neo-Zeon faction also operated ones acquired during their alliance with the Titans and after capturing Earth Federation bases. The one seen in CCA was sold after being stripped of combat equipment and programming and sold to the public. Essentially, it was a surplus sale unit that hobbyists can modify and operate.
The original North America DVD release from Bandai Entertainment included a DVD slipcover and booklet.