There are a handful of things I would need you to clarify, most of them being because I'm not fully fluent in English.
OK, here is the lowdown on how to load your live cd 
What is "lowdown" ?
(I use the term cd to also include  usb device)
Do you mean the console in the Live CD ? And what do you refer to in relation with the USB device ?
(sorry... I'd really like to understand fully) 
At grub hit the "tab" key to edit.  Add "toram" at the end of the line and hit return. 
...
To remaster with this parameter edit in "toram" to /usr/remastersys/isolinux/live.cfg as below
So, you don't edit grub boot line do you ? Is it Grub you are talking about, or isolinux ? ^_o
label live
   menu label Live
   kernel /live/vmlinuz
   append initrd=/live/initrd.img boot=live config toram quiet splash
I think you could use it to create one more boot entry instead of modifying the default live, which would offer the choice to the user:
      
  label live
         menu label Live
         kernel /live/vmlinuz
         append initrd=/live/initrd.img boot=live config quiet splash
   label To RAM
         menu label Live to RAM  // or something looking like
         kernel /live/vmlinuz
         append initrd=/live/initrd.img boot=live config toram quiet splash
... // and so on
What do you think ?