Вы должны обновить свой клиент до версии 1064. Для стим игроков это происходит автоматически, а для пираток Вот.

New Map
Thrills and Chills Amusement Park (KF-ThrillChill)

All Holiday Event Zeds Can Be Turned On
Servers (and clients acting as servers) can change a line in their KillingFloor.ini file to change what special event zeds will be in their game.
In the Killingfloor.ini, section [KFmod.KFGameType] find the line (or if it is missing admins can add it): SpecialEventType=

Valid inputs for this field are:
ET_None - Standard Specimens
ET_SummerSideshow - Summer Specimens
ET_HillbillyHorror - Halloween Specimens
ET_TwistedChristmas - Christmas Specimens

General
All event achievements have been turned on permanently

Bugs
Fixed a case of logspam that would degrade performance

For more details on the video contest check here: http://forums.tripwireinteractive.com/showthread.php?t=102612

Addendum:

MoonBase has just been updated to have the zed gun parts. Clients should grab the update automatically, servers will need to trigger it (it is an optional update).