If you were actually h4c|<7d the first thing you do is contact IMVU either through thier Help Tickets or contact them via Phone. You must have all the information that you used when you created the account. Does not matter if the information has been changed to something else once it was h4c|<7d all that matters is the information that you very first joined on. Such as the name you used, the email you used, your geo location, your CC information if you used it. Your Orginal Password. Giving them all this information will help to regain control of your account again. Once you get it back take safe guards to protect it from further hacking. There are times now that they will ask you also for verification you are the one that created the account by asking you for a copy of your DL or your passport. If you can't remember or have any of this information then your account is gone and no way to recover it.
You say you have proof of who h4c|<7d you and has your account and pics of it then use that information and send it into IMVU although it is not through thier normal reporting systems you have no choice since your account is compromised. They more then likely will take your pics and the information you have and be able to ban that person from the site so that it does not happen again or to anyone else.
REMEMBER ALWAYS SAFEGUARD YOUR ACCOUNT!!!!!
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