Hi
Interesting that you are researching the Demeza's in the Isle of Mann. They are of the same line as my step father. Christine Demeza has done a massive ammount on the line from Isaac in whitechappel through Solomon at Penshurst Mill (I have visited the site and it is very picturesque) the family properity went down a little and went in different directions. The penshurst thread disapears apart from females marrying and losing the surname. Off the top of my head I understand the one who went to IOM was in a religeous profesion. Another came here to Hastings, Grandad Richard went into the navy aged 14 after his father remarried then into submarine service. His fathers remarriage led to emigration to Australia where Christine lives. I dont have her email address to hand but its something like chrissy@bigpond so you may find her posting elsewhere. Raphael DeMeza had a site which listed her, look it up.
Regards Ted Demeza