I doubt Mat (Mat Sneap) was really related to demoscene. He's owner of Eurocom. Has some CSDB entries but i think some groups used his graphics without permission.

http://www.mobygames.com/developer/sheet/view/developerId,11224/

you are very wrong in that assumption. Mat Sneap was one of the original batch of UK c64 demo teams in the '85 - '87 period on the UK's Compunet social networking system.

He was teamed up with Psy as the Borderzone.

Many of UK c64 artists were involved in demos on Compunet prior to moving into the games industry.