I have been using Homasote for about 40 years on my layouts. I always use carpenters wood glue, then use widely spaced sheetrock screws to hold everything down tight until the glue set up. I especially use screws along any edges, and on any "heaved up" or "bubbled" areas in the center of large pieces. Back in my "cheap" days, I later removed the screws so I could use them over again. On the last 2 or 3 layouts, I just leave the screws in as it is not worth the time to save them.
Jeff