Wasn't really sure of the best forum group for this, so placing it here... There's been a few threads recently about placing stop markers too close to red signals (and there's plenty of examples of that), so along those lines, please stop making stopping points trigger only when "on or past" the point. I've been doing some CRR stuff and various points require you to stop on (<1yd) or after the stopping marker (screenshots are all from various Greenbriar turn services). In each of these cases I've also looked at the other end of the train and saw there was plenty of space between the last car and any junctions/crossings/etc. so there's clearly room to allow some sort of tolerance. I think the first screenshot was pulling ahead of a switch so you can back into a siding, but the placement of the marker leaves like 15-20 yards behind the train before the switch. In that case (we'll assume 20yds), a suitable tolerance would be stopping within ~15 yds of the stop marker and you're good to go. But stopping <5yds thinking you're good, then needing to wait until the brakes release enough you can inch forward a few feet just to trigger an objective is a poor experience and obviously unrealistic. And just to cover this point, this isn't about what points the game uses to trigger markers (your position in the cab vs. front of train), this is about needing a little more tolerance in triggering an objective on stopping.
The issue with the "spot stop markers" is that you need to ensure that the camera point is on or past the marker, and the camera point is where your head is in the cab (or a similar point at the back of the train) so you can stop as pintpoint as you like with the buffers, but you haven't got there yet... One of the quirks of the game I'm afraid