Hello Game Programmer. There is currently a bug in for the Demorec and Demoplay functions as they are causing some crashing problems. Using those functions would be ideal to setting up killcam replays as it can record all of the gameplay for playback.
If you’re concerned about performance issues with storing those values on tick, I’d suggest using a looping timer with a 0.1 second duration. In some situations, this might even be less performant than using Tick as Timers aren’t built to be called that rapidly.
As far as the TArray goes, to avoid it becoming too large, I’d suggest setting up the loop to use Push to add the array elements and dropping the last element if the array’s size reaches 10. If you only need 10 positions, getting rid of those last elements should be alright.