Welcome, feel free to ask away. Pretty friendly group here.
Probably only easy way to deal with this (since it really is a system
resource issue) is to have a small main presentation that serves as a
switchboard to all the other presentations. Then when presentation 2,
etc. ends it will close and you will be back on the switchboard
presenation which is hopefully not using tremendous system resources.
Of course you could also do it with VBA, but that might not be such an
easy solution.
Brian Reilly, PowerPoint MVP