The new skin is largely unchanged from the old one. The main difference is that the new skin supports the underlying changes that we needed to make to support new features and upcoming new features that the old skin users will not be able to participate in. Eventually, we will need to discontinue the old skins entirely. Therefore, we suggest that you try to use the new skin and start getting used to it rather than being shocked when your old skin disappears.
Thank you so much for your help and understanding as we build a better MiceChat!