We have one technician who does pretty much all of our internet camera work, I don't have a whole lot of experience with setting a system up for internet viewing.

Motions work best when not pointed directly at windows. Probably 95% of all motions commonly used today are infrared-only. Sunlight, as well as heating of the glass in the window can cause false alarms. My preferred placement for motions is in an exterior corner of a room, shooting back toward the center. Hallways are another place where you can get a lot of coverage out of a motion detector with a very low probability of false alarms.

With motion detectors, you're always trying to strike a fine balance of being sensitive enough without being too sensitive and causing false alarms. The higher-end motions use multiple sensors in a single housing, such as microwave and infrared. Both technologies have to trip at the same time in order to generate an alarm condition. These are extremely reliable, but very costly.