3. Yep, we know that we are human, no one is perfect and being humans we will occaisonally make mistakes (hopefully very minor ones). It has been a couple of years since we have made any major boo boos, which are a very painful thing / hard lesson to learn, so we test, retest and test again before releasing BPS / BPS Pro versions.
4. I was hoping you would not ask that question. ha ha ha. There are a ton of Maintenance Mode plugins as I am sure you already aware of. I have never actually used any other Maintenance Mode plugins so I don’t have any personal experience using any of them. Like all other plugin choices you want to do your homework by looking in that plugin’s support forum. Check what kinds of problems folks are having and are they getting solutions or is the plugin author not responding to questions. And of course you want to double check that the Maintenance Mode plugin you choose works with Network/Multisite Subdomain site types. Hands down Network/Multisite Subdomain sites are the most complex WordPress site types.
At some point we will get the Network/Multisite Subdomain Maintenance Mode figured out. We actually had this working in older versions of BPS using an htaccess redirect to the maintenance mode template file so we can probably do something very similar again for Subdomain sites so that that WYSIWG editor can still be used to create the maintenance mode template file, but instead of loading template file directly the older htaccess redirect method can be used again. We will see if we can get this into BPS Pro 9.4 (not 9.3).