How can the decimal separators in the attribute masks and data lists be adapted to specific countries?

The separators can be customized in the language files or in the FRMs. The language files are stored in the directory C:\GEONISSERVER\geonis<version>\languagefiles for standard installations.

The formatting in the FRMs is described in the following chapter of the documentation:

https://resources.geocom.ch/documentation/public/2021/application/GEONIS_server/EN/webhelp/index.html?gns_formatierungen.htm