The NSLock bug (http://wakaba.c3.cx/sup/kareha.pl/1151796773/492) seems to be fixed in 2.0 Alpha 3. If you want to further investigate this issue, here is the archive I used, which triggered the problem in 1.6.1 (http://vim-latex.sourceforge.net/download/latexSuite20060325.tar.gz)