Have tested B5 verses B4 in rendering.Took one of my B4 files rendered it it to took 55.23 min.Opened the same file in B5 it took 58.37 min so I guess Corel calls that improvements in rendering the only reason I see for network rendering is to hide the fact they did nothing to improve the rendering speeds .Sure their are some nice improvements call it cosmetic surgery in any case not worth the upgrade I'll stick to Metacreations version of B4 the Corel update was shit anyway and the rendering even slower after the 4.1 update