Domingo,
It can be done through the scripting interface. The trick is creating a detector for each separate stream of data (Char, Brem, Brem Secondary, Char Secondary). The scripting interface in mcSimulate3 is designed to connect many different types of detectors (Voxellated, PhiRhoZ, Generation Images, EDS-like) to the source of x-ray production (Char, Brem etc.) through the XRayTransport3 class which takes the x-rays from the generation point to the detector through any intervening material.
What you will want to do is to add more EDS-like detectors. Currently the (one) EDS detector is passed into mcSimulate3.base. The current implementation of detectors only allows a detector to accumulate one spectrum. You'll have to create multiple identical detectors (using File->Preferences) and hook each one up separately to the source you want to measure. Sources can go into multiple detectors so it is possible to collect arbitrary combinations of mechanisms. You'll need to modify mcSimulate3.base or something similar to handle multiple detectors. The code in this function should provide all the hints you need to accomplish this.
Nicholas