Some GiD examples distributed vith version 3.3.0 need to be transformed to the new version. If you get an
Error in line 2 at xxxxxxxxx.uni: system ATENA is not defined
when opening a project, go to Data-Problem Type-Atena v3 and select again the checked type, e.g. Temperature 2D. Then choose "Transform to new problemtype" (Transform, NOT Update - the latter would destroy boundary conditions). After that the project should work normally.