With my Fuji with the 10-24 I have small field of view restrictions at 10-15. 

Check the "PIR Sensitivity" parameter setting. Set the sensor level to "High" for warm ambient conditions and "Low" for cold weather use. Try setting your camera in an area where there are no heat sources in the camera's field of view. Try to set the camera on a stable and immovable object, ie: a big tree. If the person/animal is moving fast, it may move out of the camera's field of view before taking the picture. Move the camera further back or redirect the camera. 

You can flip the angle part around to the angle your want. 

Yes it does. 

I would say...a qualified "yes." You are going to have a nice wide field-of-view and sharp focus. The 40mm objectives are not going to allow a huge amount of light gathering but you will have portability and that counts for a lot - a light, sharp and accurate optic is more useful than a large and bulky choice. Even if that means giving up some "reach."