4106 is a part alias of 2959, official since 2012-03. http://www.ldraw.org/library/official/parts/4106.dat
I only get one missing part, x1742. The query http://www.ldraw.org/cgi-bin/tracker/act.../x1742.dat returns nothing, so it was never submitted to parts tracker under this name. But you find this reference at Peeron: http://www.peeron.com/inv/parts/x1742 and with the help of ldfind you quickly find the replacement part, either 58367 or the more modern, simplified 60849
I only get one missing part, x1742. The query http://www.ldraw.org/cgi-bin/tracker/act.../x1742.dat returns nothing, so it was never submitted to parts tracker under this name. But you find this reference at Peeron: http://www.peeron.com/inv/parts/x1742 and with the help of ldfind you quickly find the replacement part, either 58367 or the more modern, simplified 60849