Here's a quick look a number of the changes in this patch:
Crystals may be refunded as skills may have changed.
Bug Fixes
Missing Fire Workstations
Are now visible again
Spike Trap Navigation
It was difficult to get around spike traps in some situations (Getting caught between the spikes and a wall). It should now be substantially easier for the player to move past them.
Balancing
Large Bunkers
They are a treasure trove of goodies, so it made sense to make them a little more difficult. Zombies should be more frequent within them.
Damage Reduction (Zombies)
Previously DR was linearly based for both the player and zombies. The player had already been switched over to be percent based, the zombies are now using the same system.
Zombie Frequency
Zombies were fairly persistent at the start of the game, perhaps too much so. I've made some changes that should make them less interested in the player during the first stages of the game.