Hello Team I think this may be a bug. Selecting a map with only previews inside of it is causing an error, where possibly it should not. And if it is by design that it triggers an error, then the message it gives is not helpful. A better message would be "map cannot contain only previews" The error message. therion.exe: error -- GreenlinkArea/INDEXGLMESM_System.th [164] -- incompatible map projection -- SwissM_PlanMap@GLMESM_system The map definition. map GLMESMPreviewOnlyMap -projection plan preview below SwissM_PlanMap@GLMESM_system #map preview below DwarfsDoorPlanMap@GLMESM_system #map preview below MiddleEarthPlanMap@GLMESM_system #map endmap GLMESMPreviewOnlyMap The maps all have -projection plan explicitly defined, and the error is unchanged if I remove the projection option from the definition above. The thconfig. select QEII-01GreenLinkPlanCL select QEII-01GreenLinkPlan select GLMESMPreviewOnlyMap I have selected three maps, two contain valid maps, and one contains only previews. If I remove one of the 'preview below' statements preceding any of the previewed maps, the project compiles as expected. If I try to type the preview below directly into the thconfig, there is an error also, but I suspect this might be by design. Using 6.0.3, but am not assuming this was introduced recently. I have never tried it before. Regards Bruce