Every material can be messed up by improper storage or mishandling. Each is suited to some building techniques and unsuited for others. Homasote is excellent for folks who like to push spikes in by hand, and now that cork has turned into rubber will probably become the go to roadbed again.

pqe

When I moved to North Carolina, I was warned not to use Homasote as it apparently is hugely attractive to silverfish in the humid climate we have.  Don't know if this is actually the case, but I offer it in the event it is.

Do the bug bomb routine in the layout room every 4 months and no more silver fish or other creatures that are unwanted. We do those in the club house and it does wonders for elimination of insects. There is a residual effect that seems to kill new arrivals after the fact for several months as well.

Yes, the swelling was a problem but the warped Homosote ended up a good roadbed non-the-less.  Where the swelling occurred I had hoped that it would dry and settle down but it seemed to hold its shape. I went ahead and layed ties across the joint and then sanded them level after the glue dried. The thinner ties will not be a problem as I like the dirt and grass between the rails look anyway. Here is the area in the works. 

You can see the edges are still a mess but not a problem. Our humidity here is often 80% or more so this has worked out better than expected. Don't laugh at all my template layers!  I'm sure transferring the plan via once wheels would work but I couldn't find mine :(  777 works good with the bum wad and I still have all that stuff so ..

Neil