Hiya David,
Sorry to hear about the break in. I don't know about your area, but guess generally the old security light is a deterant.
However, where my Dad's shop is, the security light would have been better if it was not working

, as we got the impression it helped the gits see what they were doing, smashing the steel plated door in, lots of domestic windows overlooking

. And, yes they came back the next week with a car jack to bend the bars over a window, as we had somewhat reinforced the door
Best chance apparently, not definate though, of legally catching them, is cctv !
We are having the problem of do we make it look very secure, so generally its not worth attempting a break in, or does it then look like we are protecting something of great value

. When all we want is not to find a mess in every room and a smashed in door or window
infa red cctv