Oh I wonder how the platform movement is designed - I've always been cautious about the unknown nature of behaviours - I assume they are made with effeciency and performance in mind, but I do know the complexity of some behaviours is quite high (especially the Platform behaviour), which makes me very unsure about using them, as if I encounter any unwanted issues or wanted to request a change to the behaviour that is vital to my project, then it may not get updated as any update to the behaviour might break it for someone else's project.
I know that the "Custom Movement" behaviour has a "Stepping" feature, so I presume the platform behaviour uses this too - This is great but I believe this is still not as reliable as raycasting. (If not sure on definition - "Stepping" means that it will "move the object, test collisions, move object again, test collisions again" multiple times in 1 tick.) EDIT - I use a combination of both stepping + raycasting in my C2 projects, so that it handles high-speeds and collisions well, even running at the speed of 3000*dt into a 1px wall would work reliably!
To be honest I've only started experimenting with the LOS behaviour to make a raycast-based platform movement - Back in C2, I used to use the "Light" and "Trace" plugins and it worked very reliably. In C3, I have high hopes that LOS would be reliable, but I haven't nailed it down just yet, only because of having the time to check it out!
For your project right now, one possible solution you could explore would be the System event "Set Minimum Framerate", where you could choose a Framerate that you expect your game to run at (e.g. 30fps) and if someone's computer cannot reach this and say reaches 20fps, then "dt" will not increase further, meaning the player would experience a slow-motion effect if their fps falls below 30fps (which is much better than teleporting through the map! But may be bad for any games that require rhythm or precision jumping ).