A few discussion points:
(1) Is it in the eventual plan to change up how the developer contribution works? Not necessarily the amount of fee, but how it's obtained. While I love your software, it is a bit unorthodox in terms of the one 20 min block of time. Normally I wouldn't care about the one block, but here's why it matters for me.
Every day without fail my computer will freeze for some odd reason. I am not necessarily blaming HA...it could be it but I can't prove it for sure (it could also be Teamviewer screwing with me). Sometimes I'll find the machine frozen and others it'll just have basically restarted back to square one. Every time it does that, assuming I restart HA, I "reset" the developer contribution. As discussed with you before, the software is designed to get that contribution no matter how many minutes left in the day there is (generally). If there is 1 hour left in the day and you're just starting your mining for the day (or you've just rebooted your computer), it's going to donate another 20 mins no matter how many times you've already donated that day.
Today is a prime example of this. I've done (at a minimum) two 20 minute donations today. Once during the morning before my 3pm freeze/reset, and once after I rebooted (that's all I'm aware of, I haven't checked logs to see if there are other reboots in there). I actually ordered another 16 GB of RAM for my rig to see if it might help the freezing..it seems to occur upon coin switch (i.e. the "starting" of 8 different ccminer processes). I figured more RAM above and beyond my 8 GB existing would help. I want to install that right now, but if I do and restart HA, I'll donate ANOTHER 20 mins to you in the ~1 hour left before midnight. Maybe the RAM will solve my issues here and this won't be a problem anymore, but in general this doesn't seem like the ideal way to go about this.
Is there any consideration with modifying the formula to be shorter blocks (e.g. 5 mins every 6 hours of mining), or maybe a way to track on your end that we've made the required contribution for the day so that if I have to reboot, I won't be held hostage?
That is definitely not the intended behavior. The software should keep track of whether or not the dev fee has run for the day regardless of the number of times you stop and then restart it. An exception would be if you delete the .exe file or if the dev contribution is interrupted by the user or a system crash. I'll run some tests on my machines to see if stopping/restarting the software is causing the developer contribution to run more often than it should before I release 1.7.1 so I have an opportunity to fix it as soon as possible.
Since you mentioned TeamViewer, I have to ask if you had to change any settings to get Hash Auger to display properly. Some users are reporting that the software is just a blank window in TeamViewer but the problem goes away when they hook up a monitor to the rig.
(2) Separate request or question - is it possible to manually update miners without waiting for you to update HA? For example (making up versions), if the current version of HA had nevermore 2.2 and I wanted 2.4...is it just taking the download from github and replacing the files in the miner folders exactly as they are, or is there something on the back end that would prevent me in doing that? #3 is related to this...
It is possible to update the miners by editing the config files. However, if the mining software changes its screen output format, the software may not be able to parse it correctly which would probably result in some broken functionality. Also, if the miner adds algorithms, there would be other config changes that would also need to be made. However, I could probably type up some directions for advanced users such as yourself.
Speaking of Nevermore, 1.7.1 will include the new merged version of Nevermore so x16s should be a little faster.
(3) I see when ccminer pops up that it says something at the top about "cuda 8". I have 1080ti's that use "cuda 9", or at least that's what other miner or software versions tell me when they start (outside of HA). Could that be causing any stability or performance issues for me? I'm not an expert so this could easily be a dumb question.
Looking at the miner output, Xevan appears to be the only variant of CCminer that still uses Cuda8. Unfortunately, that miner has never been updated, so I don't expect that to change. You can try disabling that algorithm and see if it helps your stability issues. Is there a pattern to which algorithm(s) the software is mining when the system freezes?
(4) Any plans to build in some sort of maybe telegram or email notification when mining has stopped (so we can use corrective actions to fix it)?
Sorry for the long post, and while none of the above prevents me from using HA, these thoughts have been on my mind and thought I'd get them out there.
I definitely appreciate the feedback, especially about the developer contribution - that is something I want to address as quickly as possible. I'm definitely thinking about including support for offline notifications, I just need to setup a cloud repository for that functionality since the feature wouldn't work too well if the contact information was stored on the rig and the rig was down. Unfortunately, that means working out some security and privacy concerns before I can put it into place.