Prior to this update, special attacks were a little rough on the Melee Max Hit calculator. Only a few items were supported and the various godswords were set up oddly. This has all been revamped!
Upon selecting an item with a special attack, you no longer have to select whether you'll be using the special attack anymore. This is now handled the same way our ranged max hit calculator works - your normal max hit AND your max hit while using your special attack will both be displayed automatically. This should simplify things and overall accuracy should be improved.
Support for the Dragon Battleaxe special attack has be removed temporarily. It was inaccurate anyways, as it needs to take into account the levels of various combat skills that weren't being entered. This will be corrected and re-added at a later date. The Abyssal Bludgeon special attack will be added in the future as well.