What happens if a man was married to more than one woman when he died?
The share relating to the deceased's wife under law will be divided between his widows.  

Widows Have Equal Shares

In what proportion will inheritance intended for a deceased's spouse according to law be divided amongst his widows?
Equally. 

s a woman who is lawfully married to more than one man entitled to part of the estate?
Yes! So long as the woman is lawfully married to the deceased she is entitled to part of his estate even if she has committed the criminal offence of bigamy. 

Is a woman who is in the process of divorce entitled to part of her husband's estate?
Yes! So long as the woman is still regarded as married to the deceased, and they have not actually divorced, she is regarded as his spouse and is entitled to inherit as such. 

If a wife refuses to obey a rabbinical court judgment ordering her to divorce her husband will she still inherit if he dies?
Although in principle a widow will inherit even though she and the deceased were in the middle of divorce proceedings, in the exceptional situation whereby a wife disobeys a rabbinical court judgment ordering her to accept a 'get', then she will not be entitled to the share of her husband's estate intended for his widow.  

What happens regarding inheritance, if the rabbinical court gives a man permission to take a second wife after his current wife refuses to obey a judgment ordering her to divorce him , and he dies after marrying again?
The second wife will inherit all the share intended for the spouse under law and the first wife will get nothing.