The rules list that you are allowed 50 karma at character creation (give or take qualities).
50
Customization Karma...which you
spend on four different things (skill advancement, attribute advancement, qualities or resources) at step four of character creation (which is conveniently named
Spend Customization Karma)
There is no reason to believe they go away.
There is no reason to believe that
customization karma must be spend
while you are actually
customizing your character?
There is no reason to believe that since there are no rules
allowing you to carryover customization karma you cannot do it?
Interesting...
(I can't really say I agree with your reading or on your interpretation on how the rule structure in Shadowrun works; but it is your table, your rules).
That's how "list things that are allowed" rule systems work.
There is a list of things you can do with your customization karma. It contain 4 things and the list does not seem to be open ended. Carryover customization karma is not one of the four things you can do with them. It
used to be a thing in previous edition, but it was also
only a thing because there
was a rule explicitly
allowing you to carryover (a maximum of 7 in this case).
That because there is no explicit rule
forbidding you from carryover karma (rather than an explicit rule to
allow you to carry over karma... which would follow the normal rule structure of Shadowrun and which was also precisely what previous editions had) you think there is reason to believe that you are still
allowed to carryover up to 70
customization karma after character generation anyway?
That mean that, according to your reading at least, I can start a game at your table by
initiating up to 5 times in a row?
Since you will also not find any explicit rule
forbidding you from
initiating during chargen it must, according to your reading at least, mean that it is
allowed to also
initiate during chargen?
I will point out that there is a cap on nuyen that can be carried onward at that point. As there is a nuyen - karma exchange value in charge I take the assumption of a limit as given. But not stated directly
If the intent is that you should be allowed to carryover customization karma in SR6 then there need to be an explicit rule
allowing it (and in that case the rules as they are written would need an official errata). This is how the rule structure in Shadowrun work. In the previous edition you
were explicitly
allowed to to carryover a maximum of 7 karma. In this edition you are not.
If the intent is that you should not be allowed to carryover customization karma in SR6 then the rules as they are written are correct (and they are not in a need of errata). Having said that, since at least one person find this ambiguous it would not hurt if there was something added to clarify that you are not allowed to carryover customization karma in this edition.