FATAL ERROR: planquadrat_t::rdwr() - Error while loading game:

[Giziar]

I saved my save two weeks ago and upon reloading today I get the following error:

FATAL ERROR: planquadrat_t::rdwr() - Error while loading game: Unknown ground type '0'
Aborting program execution ...

Version: 124.3.1 (and getting the same error after downloading 124.4)

Savegame originally started somewhere 2012-ish with most likely the 110.1 version and subsequently played during quite some upgrades.

No recent edits of the save or changes of settings which could explain this error imho but a couple of edits during the previous years:
2016: Hexedit change of "maximum_intransit_percentage" https://forum.simutrans.com/index.php/topic,12849.msg152802.html#msg152802
2024: Expansion of the map from 4096*4096 to 4352*4352
2024: Change in climate https://forum.simutrans.com/index.php/topic,23230.msg208519.html#msg208519

Is my save doomed?

[ceeac]

Is the error reprodicible in 124.4.1? Can you upload the save somewhere so we can reproduce the bug?

[Giziar]

Save game (plus all pak files as I might have added some pak files over the years not in the standard pak64 pack) can be found here: https://limewire.com/d/IsmCd#CfXvg7nCLV (49MB) (link expires in one week)

And I haven't spotted the 124.4.1 version yet I must confess but getting the same error in 124.4