The only way that could happen would be if he used some of the same variable names as the shadow system.
For sure this is no slight on your system shaun, as it works like a dream on other projects I am working on. Its just one of those things. To be honest I tried fixing it for a couple of hours then get tied down doing something else so decided to leave it out. Like I say I wasnt knocking you system.
Cheers,
Unc