The exception while attempting to add new users indicates that your SMTP settings are either not set or invalid. CPAS needs a valid SMTP configuration to send email. You can set this configuration in the cpas.xml file in your Tomcat directory.
Your MS2 upload log doesn't show any errors, though based on the elapsed time (0.02 seconds) it appears to have stopped very early on. Hard to tell what the problem is from the log (we are adding more verbose MS2 upload logging in the next release), so you should probably just post a copy of your pepXML file. I've attached a small sample file you can upload as well. Note: I'm not including the FASTA file, so the loader will warn you that it can't find the file… just ignore the warning.
You can configure CPAS to load MS2 results from anywhere in the file system. You want to add a "Data Pipeline" webpart to a portal page and set it up with the root path you want. See the documentation here:
https://cpas.fhcrc.org/Wiki/home/help/page.view?name=bioModules%2FpipelineAdam