I managed to adjust the import script but due to the size I run into the next problem.
Is there a way to store the .t8 data in e.g. daily files?

To put options data for a whole year is way to much data for the 32bit memory limit. Could history files named other than ASSET_YEAR.t8 ?
Unfortunately, I did not find anything in the manual.

Can multiple .t8 file be concatinated?