Thanks for your replies guys,
I did wonder whether there were any limitations and sound like this may well be the case.
An interesting point is of misbehavior and evidence which had only recently come to light. I wouldn't know this unless I looked in to it I suppose.... I would be surprised if having invested these funds over this amount of years, there wasn't some kind of growth and given I got back what was originally invested does sound suspicious (negligence or foul play who knows). As for evidence; well, there you have it
I guess it wouldn't hurt to do a bit of investigation... I gather you can get a copy of the will from the probate service, so I could find out the original contents but is this likely to contain details of the trust? Is this is separate document or is it contained within the will?