Hi Ganesh,
My first suggestion would be to upgrade the project to 5.21.5 and try this process again. I asume you are opening the 5.19 export in the 5.19 modeler. A simple thing to check is to ensure that you are creating the project in a directory to which you have write access on your local machine. I've tried to create a Mendix project on a directory to which I could not write and recieved a similar crash.
When Mendix 'goes gaga,' does that mean it simply crashes or does a dialogue box with a 'show log' button appear for you?