To make this post submit I had to select a different plugin than the issue actually relates to. I was going to select Pro-Sites since it contains much of the functionality of Multisite Plugin Manager, but Pro-Sites did not appear in the list.
We have a site crashing conflict between Multisite Plugin Manager (Aaron's free version) and Ultimate TinyMCE Pro (Josh Lobe's paid version)
Both plugins co-exist perfectly on WP 3.8 multisite network unless we upgrade Ultimate TinyMCE Pro above version 7.3. (That is the point in time when this issue began at a lower WP version.)
Any Ultimate TinyMCE Pro upgrade above v7.3 crashes the site and only removal of one or the other plugin will restore site functionality. After restoring version 7.3 of Ultimate TinyMCE Pro they co-exist fine.
I have deactivated all plugins on a test site except these two and have confirmed that the site crashing conflict is between them.
I have reported this issue here:
And in September I reported this issue here:
I realize these are not WPMUDEV plugins although Multisite Plugin Manager contains much functionality similar to Pro-Sites, but would appreciate any assistance to get these two great plugins co-existing again.