If you can't see the link to "Modeling Time and Position Varying Mass Properties" inside the third link, that is the way to go. The model attached to that model should tell you all you need. In short:
A massless part is attached to the "rocket" (I call it rocket as that is the most common application for this) with a translational joint and a motion (only if cg-variation is only a function of time, otherwise use a GCON). On this massless part that represents the CG of the rocket a GFORCE is attached. The GFORCE has the function F=-m*a (in all six components, you have to work out the functions for the rotations if they are of interest to you). m is the varying mass.
The technical paper on 'Modeling time and position varying mass properties' was helpful, but the .adm file doesn't contain any parts as referred in the .txt file, only a translation joint with a motion was imported through .adm. Even the forces mentioned in the paper were not imported. Tried importing in older versions as well 2017.2, 2019 and newest 2023.2 its the same. Please check at your end.
