Status: Fixed version of ONML has been uploaded: http://www.neolemmix.com/old/neolemmix/OhNoMoreLemmings.nxp
As reported here (http://www.lemmingsforums.net/index.php?topic=2472.0), Havoc 14 appears to be impossible - certianly, the standard solution doesn't work - on NeoLemmix, due mostly to the difference in basher mechanics. There's also a less-major problem with the entrance position in the top-left.
Fixed version has now been uploaded.