AlienBOB stopped coming by the linuxquestions forums some time in 2021. If you want to ask him questions, you're better off posting on his blog or trying an email, though you should try the following first, which is how his isos are made:
1. Get a copy/clone his 'liveslak' repo. E.g:
https://slackware.nl/people/alien/liveslak/
These are the scripts he uses to create the Slackware Live isos. The one you are interested in is called 'make_slackware_live.sh', and more importantly its config file 'make_slackware_live.conf'
His scripts are well documented and you will learn how to use them by reading the comments, particularly the config file, which is what you edit to make a custom iso.
2. Edit the 'make_slackware_live.conf' file, which is a list of the options that a user wanting a custom iso might want to tweak. Take a look at SEQ_CUSTOM:
Code:
# REQUIRED:
# Define your own custom package sequence for a custom Live ISO.
# In this example you would need to create two files "pkglists/cinelerra.conf"
# and "pkglists/cinelerra.lst" defining the package location and package list
# respectively):
#SEQ_CUSTOM="min,noxbase,x_base,xapbase,xfcebase,cinelerra"
So make your package lists in the same format as the other package lists that the comment mentions, and set that variable appropriately. If they are already slackware packages then I believe it is enough to just make the .lst file. Custom packages from another repo will need the additional .conf file to direct the script to the repo. Look at the existing .lst and .conf files in pkglists/ to see how they work.
3. Run the 'make_slackware_live.sh' script, which uses your custom package lists and wait for the script to make the iso.
Whether or not your package list makes a viable system is another question and I didn't bother to look too closely at your list. Some tracking down of dependencies may be needed.
HTH
Edit: I read the original post as wanting to build a live iso, but I suppose you just wanted installation medium. I'll leave this post as is for posterity since I realized it later. Hopefully one of these options in this thread are what you want.