By default, DITA2Go uses XML catalogs to resolve paths to resources. Because DITA 1.2 depends on catalogs so heavily, your DITA document should use XML catalogs to locate DTD, system entity, or stylesheet files.
To specify keys to each XML catalog:
[Catalogs] ; UseCatalogs = Yes (default, resolve paths to resources ; via specified XML catalogs) or No UseCatalogs = Yes ; CatalogKeys = list of keys to local XML catalogs CatalogKeys = dita1.2 dita1.1
Catalog key names are arbitrary. Several catalog keys are already defined in site-wide system file %OMSYSHOME%\common\system\config\omsys.ini. Put your own catalog key names in %OMSYSHOME%\common\local\config\local_omsys.ini, because the corresponding system file is replaced during updates.
[Catalogs] catalogkey = path/to/local/catalog.xml ; Use forward slashes, not backslashes in all these paths: dita1.1 = %omsyshome%/d2g/dtds/dita1.1/catalog-dita.xml ; Use this key instead of dita1.1 if you want 1.2 features: dita1.2 = %omsyshome%/d2g/dtds/dita1.2/catalog-dita.xml ; This key supports the DITA4Publihers specialization: d4pubs = %omsyshome%/d2g/specializations/d4pubs/dtds/d2g_catalog.xml
Note: Use only forward slashes in catalog paths, not backslashes.
For example, in local_omsys.ini:
[Catalogs] mydoc = D:/mydtds/mydoctypes/catalog.xml myxml = D:/mydtds/myxmldomain.doctypes/dtd/catalog.xml
And in your project configuration file:
[Catalogs] CatalogKeys = mydoc myxml dita1.1
You can define all the catalog keys for any resource you might ever want in top-level configuration file local_omsys.ini (see §1.3.7 Establish system-wide configuration settings), then use whichever keys are appropriate on a per-project basis, in whatever order you require for each project.