I just opened an "older" sequence I did from earlier this year in XL4, and my chases are still functioning just fine. I have 4 arches, each defined as their own individual models, set as part of my display. I then have a model defined as a single line, encompassing all of the channel numbers from the four arches, and not part of my display. Any time I want to do a chase on all of the arches (1-4) as if they were one model, I drop my effect on that single line model. I have two additional models based on that one, (1-2) and (3-4) so that I could do separate effects as if I only had two arches.
I've used the SingleStrand and Curtain effects to create a chase. With the SingleStrand effect, make sure the cycles field is set high enough to create moment. That field is the equivalent of selecting a speed.
Hope that all makes sense?