What I mean is, that when
booting the live ISO, there is a screen right at the beginning to choose from. You can press Tab there and edit the boot line. Usually it contains something like "initrd=/live/initrd.img boot=live ip=frommedia union=aufs vga=current" or similar. There you can append "netboot=cifs" to make the network share mounting active. If this happens, the script 9990-mount-cifs will be run, else it's not read by live-boot.
I am aware you 'could make it work for yourself' by adding mount commands (that probably override secrets management), so I try to help you make it work 'for everyone' by using the existing tools that Debian ships for these cases. You also mentioned in your note that you "don't want to take days to figure this out", so I think we can figure this out in less time, together ;)
Of course it's a mandatory exercise, I won't send you the Russian mafia if you don't tinker with it :)
EXISTING LIVE SESSION:
in the ISOLINUX boot screen, press Tab and append "netboot=cifs", also add the stuff that is written in the manpage:
netboot[=nfs|cifs]
This tells live-boot to perform a network mount. The parameter
"nfsroot=" (with optional "nfsopts="), should specify where is the
location of the root filesystem. With no args, will try cifs
first, and if it fails nfs.
so, something like:
netboot=cifs nfsroot=//${server}/${share}/ nfsopts=user=username,pass=pwassword
then boot it and check if live-boot stops while mounting the shares, asking you for the password - I'd be interested to see how this is managed inside of live-boot. I can't imagine 9990-mount-cifs being edited to mount a specific user and having a hard-coded password inside, so there must be some mechanism (which I unfortunately cannot check!)
IF IT WORKS AND YOU CREATE A NEW REMASTER:
0) keep the 9990-mount-cifs (default)
1) edit the /usr/lib/bbqsnapshot/iso/isolinux/isolinux.cfg and
add the string above behind every occurrence of "append"
2) create a snapshot (the edit of the previous step is then written onto your new ISO)
3) test it and mark the topic as "solved" ;)
As said, if you are not interested in this, just ignore and do it your way :)