Hi Web,
We put in our vinyl pool last season, but didn't do the deck until about April of this year. We have no cracking at this point but it has only been one season. We will see what the winter brings. I'm not sure you should see cracks this soon if they settled the surrounding dirt correctly. Also, we have a safety cover and our handrails are solid in the galvanized sleeves. They can still take them out and tighten them back up when we put them back in next season.

Good-luck!