It seems that I have been correct about my interpretation of the RMU binaries; the RMU is, as a matter of fact, an engine similar to the vPro engine. The binary provided by Intel that is required by the RMU is what the Intel Architecture Manual Volume 1 describes as the Microcode Update Facilities. The Quark's RMU works in such a way that the firmware programmer doesn't have to worry too much about the process of updating the microcode. The programmer still has to provide the address at which the microcode is placed in RAM after memory initialization, but the RMU takes care of decoding and interpreting this code.
Read the Intel® 64 and IA-32 Architectures Software Developer’s Manual, Volume 1, Section 9.11