1. The README describes exactly how to upgrade from an earlier version to the current version of uddeIM. This should be possible for every Joomla administrator.
2. It IS your servers' problem. You are wrong when you think your VPS server has lots of capacity and is reliable: "The host company tells me I have exceeded the limits of the CPU, but this only happens when I click on uddeIM."
Sure, uddeIM provides several features but is not that complex that it utilizes the CPU completely, e.g. it is running here on Joomlapolis and this site has over 350,000 members. I am pretty sure that are more members then you site will ever have.
I suggest you are looking for a hosting company that provides a reliable service. I know several admins who are hosting on a 5 EUR shared server from all-inkl.com which means that the resources are shared with several hundred other sites... and guess: they have no problems, even with sites >5,000 members.
uddeIM & uddePF Development
CB Language Workgroup
CB 3rd Party Developer