I am trying to slice an object with 14 million polygons but it won't complete the slicing process. Is it not capable or could it be some other issue?
14 million is a lot. So you need much time and even more ram. Check in task manager how free ram goes down. As soon as you start to swap memory to disk you are lost. Also makre sure you have NOT enabled "Prevent crossing perimeter" this is a very time consuming task especially with bigger models.