While snooping around the stock init script, I spotted a variable, home, in the mountdata function standing out from the crowd. After doing some quick tests, the preliminary results are summarised as follows,
Prerequisite: The persistent overlay (.img, .aes or .inf) being on the same partition as the KNOPPIX file.
Functionality: Loading a specific persistent overlay at the boot time.
Usage: knoppix home=/mnt-system/foobar/dummy
*The dirname and basename cannot contain any whitespace characters.
*The basename needs to be unique if there are more than one overlay files in the same folder because the suffix cannot be part of the argument.
[ Bulk Of 21 ] Intel Core i7 4790 3.6GHz Quad Core CPU Processor SR1QF LGA 1150
$776.79
Intel - Core i9-12900K Desktop Processor 16 (8P+8E) Cores up to 5.2 GHz Unloc...
$619.99
Intel - Core i7-12700K Desktop Processor 12 (8P+4E) Cores up to 5.0 GHz Unloc...
$419.99
Intel Xeon E5-2697A V4 2.6GHz CPU Processor 16-Core Socket LGA2011 SR2K1
$39.99
Intel Core i5-8500 3 GHz 8 GT/s LGA 1151 Desktop CPU Processor SR3XE
$49.99
Intel - Core i9-14900K 14th Gen 24-Core 32-Thread - 4.4GHz (6.0GHz Turbo) Soc...
$619.99
Intel Core i5-12600K Processor (4.9 GHz, 10 Cores, FCLGA1700) Box
$164.99
Intel Core i5-12600KF Desktop Processor 10 (6P+4E) Cores up to 4.9 GHz Unlocked.
$145.59
[Lot of 4] Intel core i7-4770 SR149 3.40 GHZ Processor
$135.96
Intel Core i5-6500T SR2L8 2.50GHz Processor | Grade A
$25.00