Does anyone first set up Fluid Boxes much like a wireframe before hand?

I'm just curious, does anyone first set up their Adobe Captivate 2017 fluid boxes before putting the content in, much like you would a wireframe for a website?

i'm thinking, I would put in Lorem Ipsum where much of the content would go, then place holders where the images would go, as a way of making sure it all works before hand. 

Does anyone else work this way?