UV Lightbox Timer

[Dagwood]

Hi All
This is my first post and am fairly new to all this and wondered if anyone could help?
I am in the process of making a UV light box for PCB exposure using an old scanner and a fair few LED's, this part is working fine. I then decided to add a timer and found this site 5 to 30 Minute Timer.
I have copied the schematic aside from changing R1-R6 to suit the time delay I require as per the formula and added a couple of voltage regulators, one to power the circuit and the other to power the UV led's. All seems to work except that the relay latches as soon as the circuit is power up? I have check all solder joints and know the answer is staring at me, I just can't see it!
I attach a scanned copy of my PCB layout for clues.

Any advise would be great.

Thanks