I am making a small, very basic animation to learn the basics of Animate CC. So far I have two layers; the first layer is the 'rough draft' layer in which the brushstrokes are messy. The second layer is the lineart layer where I tried recreating the first layer with smoother and cleaner lines; because I wasn't getting smooth lines with the brush tool, I began using the pen tool. However, when I play back the lineart layer it pauses on each new keyframe I've made. This only happens to the layer with pen strokes. Just to make sure this was the case, I created a third layer with a separate animation just using the brush tool, and that separate animation played smoothly when I disabled the previous two layers. Is there anyway to convert the pen paths to brush strokes? I just started using Animate CC, so there are many things I still don't know.
i don't understand why you're seeing a problem, but you can convert lines to fills (modify>shape>lines to fills) and see if that makes a difference.