Rudolf Stember is a German composer and sound designer who worked for Factor 5 since the mid 90s. 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, whose driver was later modified (possibly by Stember) to allow fading and relocation. Both music editors were commercially released on the same disk.
Stember often used a low-pass filter on bass instruments. However, the filter varies with every SID chip and the bass may be too loud on some of them. In VICE 3.2, most of his C64 game music sounds good with the model 6581 (ReSID) and a filter bias of -400, but it is unconfirmed how close it is to the SID chip(s) Stember used.
Circa 2007. Making of Lair.