Your post appears well documented but has not yet received any response. I am replying to raise awareness. Hopefully, another community member will be able to help.
Also, feel free to add any additional information you think might be relevant.
In Creo Simulate and Mechanism, coordinate systems can be a bit tricky because they shift depending on whether you are looking at inputs or result measures.
When you are measuring reaction forces in the XY domain, here is how Creo typically handles the Coordinate System (CSYS):
By default, reaction forces are reported in theWorld Coordinate System (WCS), which is the default assembly coordinate system, unless you have explicitly defined a local CSYS for that specific measure.
Creo does not default reaction force results to the COG of a rigid body.
Mass Properties are calculated at the COG.
Inertial Forces are often calculated through the COG.
Reaction Forces (at supports or joints) are reported at the point of constraint, relative to the WCS.
Example: If your assembly is oriented such that the "Global Y" is vertical, but your rigid body is rotated, a "Default" XY measure will follow the assembly's floor/walls, not the tilted body's axes.
