With WinDev 12 PC Soft decided to make the WinDev 11 - RAD-model still available but stopped changeability of .MDL-files ! Thee menu item
Workshop .. Custom RAD Pattern has been discontinued. Trying to open any .MDL file using WinDev 12 will open it for a view but any change will crash WinDev 12 completely.
So, if you want to apply changes to WD11-RAD, which is the only usable RAD for commercial applications now, you have to have WinDev 11 on your computer and you have to open the MDL-files of WD12 with WD11.
Kind regards,
Jimbo