It is working the exact same buggy way for me as well. Goes fine when the ties’ CanCollide is set to false, doesn’t go if they are set to true. I tried setting it to true while one of the wheels is inside a tie and it really acts like as if they are supposed to collide with each other (even though they are not).
It’s weird because me and 2 of my friends have started experiencing a similar issue recently.
Probably embarrassing for me to say, but I only recently found out about Collision Groups, so I never actually used them before. On Tuesday, I was just casually working on my tram, then concluded the day, didn’t change anything else, just building and improving that one tram. On Wednesday when I opened the same place where I make all my buses and trams, I couldn’t select anything except for a backup tram model. I checked DevForums and then found out it’s something about Collision Groups. But I still don’t know what to do or what the exact problem is… everything in the place is set to the Default one.
Later, I got reports for my main game that the AI train that’s supposed to spawn every 15-30 minutes piled up and as they kept spawning, by time there were 6-7 of them just stuck behind each other. I’m guessing that the first hit something that it’s CanCollide was magically turned on (even though we haven’t updated the game for the past 2-3 weeks), then the others just got stuck behind.
I’ve disabled the train spawning as I didn’t really have much time to do proper bug fixing and it was a pretty game-breaking bug, but since then the main game is also now experiencing the same weird bug that occured in my bus/tram making place. In the main game, it’s about half of the map acting normal and the other half can’t be selected in Studio and that part acts like it’s not supposed to collide with anything. There is a bus garage on both sides. You can walk safely on both sides. Those buses that can be spawned in the buggy section just completely fall out of the map like 80% of the time. In the other 20%, they stay and act like the ones on the other section, which is that they fall out once you get out of them and only if you are on the bugged side of the map.
I actually tried checking the “border” of the 2 sides with an articulated bus. Sure enough, when I jumped out of the driver seat, the front was fine, but the part after the bendy part was just swinging in the baseplate itself. Both sides and the bus are all on the Default Collision Group, and all 3 had their CanCollide on.
To fix the bug, I first tried restarting Studio, didn’t work. I then tried reinstalling it, didn’t work. I tried restarting my whole computer, still didn’t work. I also tried making a script that sets everything in a new Collision Group that can collide with Default and itself, but it still didn’t work. The only thing that worked so far that can speed up my production is putting things in a completely new baseplate, but that’s really not ideal especially when it comes to big maps. And who knows when will that also bug out.
From what I have seen so far, it’s almost as if it put itself in a separate Collision Group that can’t be edited, doesn’t collide with anything, and shows itself as Default even though it’s not. And even a script couldn’t change the part’s CollisionGroup properly. I mean, it did change it, but it acted as if nothing happened.
As for plugins, I have “Team Create with Hats” installed that adds an extra CollisionGroup, but even in places where Team Create isn’t turned on and the plugin doesn’t do anything, the bug still occurs. The 2 friends that I mentioned at the start don’t even have the plugin and the same occurred for them.
It’s pretty frustrating as it’s a pretty game breaking bug and it also slows down production very heavily. We still have a Christmas update and a map update to make until February and I already think we are late.