Issue with changing payload cart models

[MayorMars]

I'm trying to make a payload race map, and I want to change the models of the bombs from the plr assets to something else. I tried with a fridge to see what it'd look like, but the fridge model stays where its placed in hammer instead of snapping into the track like the unmodified blue bomb did. How do I change the model of the bomb?

 

[Kill_the_Bug]

check to see if the fidge has the peop_dynamic feature in the checkmrks checked - it yes you can use it if no then it's just a prop_static and can't be used