Every firewall and AV, or almost every, hates the others.
Not to spite you, but to be able to work properly.
At issue is simply too many cooks in the kitchen trying to get at the same thing.
Driver conflicts abound. To be good, these applications have to use their own drivers at a very low level.
Have you used Norton removal tool before installing ZA?http://www.bleepingcomputer.com/forums/t/34671/how-to-remove-your-norton-products/
If you used the already spoiled and bloated restore CD from the manufacturer, as you seem to indicate, then likely Norton got pushed in already. (Yes it's criminal of them to put in software you don't ask for, and even more criminal to leave stuff behind when you get rid of it, but what can you do?). Restore CDs don't even offer a reformat, just the quick format
Some have claimed that the Norton stuff installed without your consent is actually a rootkit, in which case ZA's Kaspersky AV (within ZA-pro and suite) is doing a good job.
Removal is very difficult. I don't know the details.
What do you mean "it was flagged by VBA32" what is VBA32?