Thanks for replying so quick. I'm using a lighting design program called Softplot9 3D. The builders, all though they try, haven't been able to find the problem, so getting a different set of eyes on it was my call. And your suggestion had not been put up yet. Yes, I am using Avast, I'll disable that and let you know how it goes. If it works, can I pass on your solution to the builders?
Thanks again for your help, appreciate it.
Cheers.