First let me start by stating your goal is not something someone with little or no programming is going to be able to do (at least not for a long time and alot of hard work). If you don’t know the basics of client/server & network protocols, you have alot of learning. Reverse engineering a software is no easy task (or knock off paltalk clients would be readily availible). Some people have done it in the past, and some people will do it again in the future, but it is not a job doable by just any one. Start small and do achivable projects on your way to reaching your goal. Do not expect that you will have a working knock off client in a month or 2. If you had one in a year, you would be fast!
As far as modifying the original paltalk program code, you can do some of that (but it has its own limits and challenges). The problem with making a new client is that so many of the “features” are now being controlled by the server. The biggest advantage of making a knockoff client is that it could be made with a language & compiler that is cross-platform compatible (windows, linux, or mac).
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