The first question you should ask is, Does IMVU forbid the use of an aftermarket client and if they do what are the specific terms of service as it relates to a user actually doing this. Many online platforms, including Second Life, are accessed by use of aftermarket clients. This is a fairly common practice and begs the question, Does IMVU Actually Forbid the use of anything other than their propitiatory client. IMVU Publishes a TOS and other platform rules on their site.