Dan and Michael have suggested excellent ways to deal with the Halloween lighting. I do not use AHP anymore having moved up to Homeseer, however if you have "SmartMacros" you can use a conditional to enable/disable all or select timers.
You need to create a "permissive" switch. Select an unused House Code/Unit Code (for AHP, if I remember, it will have to be a "monitored" house code if you store in the interface) and within each timer macro add a conditional that this HCUC must be ON for the macro to run. Now you can simply turn ON or OFF that "permissive" to enable or disable your timing macros. The permissive(s) can be controlled by another timer, or manually from any X10 controller.
I have permissives for all my regular timed events and some triggered events: inside accent lighting, outside accent lighting, coffee in the morning, announcements, etc. It just allows easy control of automatic events.