Problem adding new core building in RTW 1.5

I'm trying to add a new level of core building (a copy of the imperial palace for testing) I added it to the level line, copied and correctly placed. The new building is a split upgrade to I added it as a second upgrade option to the proconsuls palace. I added appropriate changed to descr_ui_building.txt, export_descr_buildings_enum.txt and text/export_building.txt

When I run Rome and exit to desktop I get the following error with -show_err and have no idea how to fix it:

Quote:

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Script Error in data/export_descr_building.txt at line 3502, column 2

Building DB Error culture db max settlements level differs from building db max settlement level for faction romans_julii (bld invalid_level vs clt huge_city)

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Any help would be appreciated.

Thanks,

Erm..you cannot add new levels of hardcoded buildings. You probably meant to simulate it by using a new complex of "government" buildings to govern the nature and potential of the settlement in which they are built. Download and take a look at how some mods do this, such as EB.