I have a few NVIDIA rigs and I've experienced the same thing. If the miner gets stuck the watchdog tries to restart it but there's a popup error that says it can't find start.bat (if that helps any).
There's a new small problem:
The node and miner will eventually stop (at least when using ewbf-zec) and the node software complains that there is a "Big log file, restart client and clear logs..". This miner has 6 NVIDIA Geforce GTX 1070s running ewbf-zec. Looks like the size of the log "package" its sending is about 5 MB. I deleted the miner.txt file in the ewbf-zec client folder and that seems to have fixed it. Seems you may need to automate that house cleaning task.
Thanks!
Update to v2.6, I hope this release will be more stable with ewbf.
1 minerstat user donated me a Nvidia 1060 gpu. So, The next release (v2.7) comes with huge nvidia support. Algos, Profit switch and more.. (I release the new version today)
Yes. I will do that.