Here are 2 trainers (cheats). The top one is in French unfortunately, but It is not that hard to figure out. The second link is to a much more powerful trainer that is not just limited to Tetrinet, it is in English fortunately.
http://perso.club-internet.fr/billyboy/cheats/tetrinet.zip
http://perso.club-internet.fr/billyboy/cheats/MTC124E.zip