With TMDL, the .bim files are removed. So make sure to activate the project files without the current TMDL preview. I just recently updated the C# PIMP script. So you can use the script also directly against the PBI Desktop model without the need to save, reopen and replace the .bim file. The script will than not add PQ tables, but it will add calculated tables such as date dimension or calc groups or explicit measure creation or empty measure table as calc tableall still possible! Alternatively you could also try to save it as folder that could work as well. With TMDL and the new upcomming PBIR folder scructure the whole process becomes even better. We can do now even with PowerShell simple copy+paste and search+replace scripts. I created one "IBCS Power BI Generator" for this. For any additional question feel free to let us know.