Need advice about late Mothers loans and shares.

My Mother who passed away a few years ago had invested a large amount of money into a property company in Spain, she had also given them a loan to be paid back by 2012. I contacted the company recently about the loan, which they denied happened. Thankfully I have some paperwork to back it up, although they are still being very vague. They said the loan could not be paid back because the company has no money. Is there anything I can do?? I know they haven't been selling much property because of the current property slump so I won't get money from the shares - but is the loan different. I Live in the UK so i'm finding it very difficult to get information....any advice would be very welcome. I hate the thought of my mother life saving being lost!