Problems updating external ip address, dmesg showing segfaults, unable to "Edit Virtual Server" for 3 domains...

System specs:
Debian 8.8
Webmin version 1.844
Usermin version 1.711
Virtualmin version 5.99
Theme version Authentic Theme 18.49-8
Kernel and CPU Linux 3.16.0-4-amd64 on x86_64

I don't know if I should ask for help separately, but I suspect they are somehow all related...
1. A few weeks ago I discovered that 3 domains would not let me edit them, only showing a link to the domain web page. The arrow was up and would not drop down to show the rest of the dialogue window. I am signed in as root. All the subdomains and the rest of the domains work as expected.
2. I made a network configuration change that resulted in a new public IP address. Going into Virtualmin->Addresses and Networkingj->Change IP Address I selected External Address, specified the original and the new IP addresses, All Servers (even selecting individual servers failed), then clicking on Change Now would show:

and then stop running. The domain would be randomly different, unless I chose a specific domain. Sometimes it will only show the first line and not the second indicating the DNS was being updated.
3. I was working on something else, and needed to run dmesg which showed hundreds or maybe even thousands of the following lines: [545724.494535] /usr/share/webm[25960]: segfault at 0 ip 00007f90069a0d8e sp 00007ffc22627a78 error 4 in libc-2.19.so[7f900690f000+1a1000]
Which I am definitely certain is the same issue as #2.

Is anyone available to help or provide suggestions on what I can do to resolve these issues? I can probably find all the places I need to change to get my sites back up and working, but don't want to miss any of them.
Thanks,
Joel

[EDIT]
4. A number of pages give me a Secure Connection Failed when accessing or redirected to those pages, such as after trying to add a new domain or manage the MySQL server...