Rudolf Stember is a German composer and sound designer who worked for Factor 5 since the mid 90's. He composed a score of C64 and Amiga soundtracks.
Stember used TFMX.
On The Tower of Terror, Stember used Audio Effect Editor, which was programmed by the same person as the game was. Apart from that, he used Soundmaster V3.1. Both music editors were commercially released on the same disk.