The nightrain is posessed again The alarm arms for no reason It has 4" over forks so sits on a fair angle when on the stand

Once the key is turned on and off again it seems fine has anyone any idea what might be the problem??

Is it a pre 07 bike? Try:
i149.photobucket.com/albums/s45/bills985/alarmsensitivityadjustment.jpg

Or stick something under the stand and see if the angle helps.
Make sure your battery and connections are in good nic.
And make sure there are no animals tripping the alarm. My dog was making a kennel out of my bike cover - took me a while to figure out what was going on...