I guess it's possible something has changed, as I've been out of Trainz for about a year, but there are a number of older crossing assets, in particular the BNSF50 ones, that do not respond to TRC script commands correctly because of the extra features they have such as the gate delay. For this reason I still use almost exclusively ATLS crossing triggers in level crossing mode even though it requires four triggers on a two-way running track, (which gets SUPER fun working with multiple tracks...)
As the BNSF50 crossing assets are much more realistic and prototypical for US crossings than the limited selection of TRC ones, it is what it is. There are now some bugs in those as well since boat updated them to a scripted control, but they've only presented in a few cases I posted about last year. If you still use the older invisible train based slaves, they're fine until N3V removes the invisible trains from Trainz.
The asset OP refers to is ATLS-TRC compatable Slave(TF) <KUID2:739738:101421:2> on DLS that I've tried playing with but I've never gotten it to work properly and there's no documentation on it. Is it supposed to be named like a TRC asset and use an invisible rail connection to ATLS-style crossing assets (NRC gates/lights?) or is it supposed to somehow take an ATLS trigger input and activate TRC crossing assets (gates, etc)? I've never found out, because both ways I tried it I couldn't get it to work.
