Tried similar settings, and from the other How to Mine Vertcoin thread... with my 7970/280x i still get HW errors. On an i7 3770k desktop with 8gigs of ram, I cant get above i=12... very strange.
Are you using the VERTMINER version I posted above? Did you just skip to my settings/configs..? Read everything maybe you missed something
Had the same problem with intensities with the older miners. This one seems to work perfectly