OS X 10.4 only went up to 10.4.11 so I would be a little leary of something claiming to be 10.4.12 and 10.4.13
I would probably be better if you were to repair your software update component of 10.4 by doing an Archive and Install of the system.
This would place a new system onto your computer and you would then update it to 10.4.11
Make sure you have a good backup before you start, just in case something untoward happens during the install. Power failure maybe.
P
Since my software update does not work I downloaded both updates 10.4.12 and 10.4.13 to my desktop directly from Apple support.
My question is how do you installl both are combos too. In the past every updatelaunched it's own installer package that first checked whether that particular update could be install on top of previous version. These updates appear to be scripts only.
When I double click the script an app I assume a script one bounces a bit on my dock then quits . Does any one know how to actually complete thes updatesOK I for any insights on this.

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