Running Remastersys On A Live Distro and Command Line Options

[tigerarmy]

I just found out that I could boot a freshly downloaded Ubuntu Live disk, upgrade it, make customizations, run Remastersys and have myself a custom iso without ever installing!   A few tweaks are needed, but I'm really happy it's possible.  If anyone is intersted, I could elaborate more on neccessary tweaks.

Anyway, with that in mind, I want to Remastersys from the command line, because I'm writing a script that customizes an iso fresh from Unbuntu.  But, unlike the gui, the man page does not give me an option to set the build directory.  Is there a way to do this on the command line?  It will not build on the live system's filesystem.  Is there a tweak, if not?