Afternoon jazzgirl,
Just been reading your concerned post and am wondering if the rogue hacker as got into your actual email, bear with me for this because it is quite easy to create a similar forum name by making a small change in the name that appears on-screen. All you actually need to do is enter the Crossword Solver site at source and then register, then just pop in the forum name you require (for instance, I could go on now with a new email address and enter under Les 40 with a space) Because it is different to my Les40, it will accept the name. There are many tiny changes a rogue contact could make for recognition purposes, like change a lower case to a capital or just pop in a full stop at the end, it's like email addresses, a dash, a dot, a space or a letter change makes the whole address completely unique. If this person has got into your actual email address, then that is someone who knows much more about computer hacking than they should and must be viewed as extremely dangerous, especially if they are hacking for personal information details.
If you get a reply from the forum hierarchy, then please tell them to contact the relevant DATA Protection Authorities. Or even go to on-line Data Protection links to find out information and what can be done, I will have a look for you too later, but I'm gonna be away from the computer for an hour or so now.
Hope that helps, Les40