Custom variant of Kali-Light for remotely supported forensic collections

Kali version: 2018.1
Kali installation:VirtualBox VM (with *lots* of resources)
Skill level: Meddling amateur

I am trying tocreate a variant of Kali-Light that I can use to support forensic diskcollections at remote locations with limited bandwith. The target machine isbooted using the custom ISO, the IP address is then sent to the forensic expertwho creates a disk-image over RDP, exporting the data to a drive that can beshipped for processing.

The default buildprocess works fine but I am having problems customizing. My requirements are:

1) ISO must be assmall as possible for transfer to limited-bandwith locations.
2) The only toolsrequired are XRDP and GUYMAGER
3) ISO should bootonly to "Live-Forensic" mode
4) Ideally XRDPshould start on boot.
5) root passwordshould be pre-set to something other than "toor"

(1) Small size is easyusing the documentation. Using --variant light gives me around 880mb.

(2) By editing /kali-config/variant-light/package-lists/kali.list.chroot allows me toadd and remove applications. Guymager is trivial to add. However around 3 years ago I created a similar Kali ISO and just added XRDP. But it now seems there are lots of dependencies needed and pre-configuration. For example: https://forums.kali.org/showthread.p...AWS-Kali-image. I am at a loss on this. Suggestions welcome.

(3) Documentationand searching tells me that grub.cfg contains the boot menu, but after runninga build, there are at least 3 or 4 versions in different paths that I couldedit. Which do I change? I have tried editing each individually or all I couldfind at the same time, but it still creates an ISO with all the default bootmenu options - my edits seem to be ignored. What am I missing? Do I need to worry about the words contained in /root/live-build-config/chroot/usr/share/kali-defaults/setup-noautomount which says this is disabled when logging in to the GUI. The system will be a live OS, so do I worry about such changes?

(4) XRDP startingautomatically is nice to have, but not essential.

(5) I think I canmodify the shadow file. Where do I put it to

TL:DR
How do I edit theboot menu?
How do pre-install xrdp and have it work properly? (Starting automatically is nice, but I can easily ask On-Site to run "service xrdp start", so it's not essential.)
Cheeky lastquestion: Any other tips to cut down the total ISO size?

Appreciate all the great work here... hope someone can help!