I am trying to get iMessage work on VMware , but the ROM value won't change

I try to pass efi.nvram.var.ROM parameter but it doesn't work and shows me some different but consistent after every boot ROM vaalue in iMessagedebug . I used this https://github.com/toshmatik/VMWare-iMessage/blob/master/instructions.md and few other guides to get everything to work , SMUUID , Serial no. everything is as i wanted and consistent just need ROM value to change