How to mesh a hollowed sphere

Hello,

I'm involved to mesh the attached solid model in order to optimize a three dimensional node. It's a hollowed sphere cutted on the top and some random holes. The point is the model doesn't present symmetries. How can I mesh this solid? First of all, at the beginning I find an edge problem showed. 

Can someone please lead me in this particular process?

Thanks.

 

Alberto

<?xml version="1.0" encoding="UTF-8"?>

<?xml version="1.0" encoding="UTF-8"?>

<?xml version="1.0" encoding="UTF-8"?>