FYI I would advise people who want to update their Inovelli devices DO NOT use this driver. It will brick your device if using the incorrect firmware or may also brick if something goes wrong.
I would use a Z-Wave stick with the Silicon Devices application to do it. Supposedly the new C-7 hub has it built in but I can't verify if it works properly. There is no way to restore these devices other than to re-flash the firmware which cannot be done by users.
I'm sorry that your devices got bricked, but there's been a multitude of devices, including many iNovelli devices, which have been updated using @bcopeland's z-wave firmware updater on C-5, C-4, and C-3 hubs. So, device bricking would not appear to be a consistently common observation.
There are also some that have been bricked. Perhaps there is a hash verification on the new firmware but if a user inadvertently uses the wrong firmware it will happen. I believe that may have been in my case but it started to flash then hung-up after waiting over an hour and never completed updating and destroyed my dimmer.
I submitted a ticket to inovelli about this but they wont replace the device or do anything for me. They said their warranty doesn't cover bad firmware flashes.
Pretty crappy that these arguably over-price devices (ie Zooz with an added LED) dont have simple protection from flashing the wrong firmware.
Zwave doesn't have a method for identifying a "correct" firmware for a device during the OTA process. It can check manufacturer and the firmware ID but those don't prevent you from flashing another device's firmware from the same manufacturer. It also has checksum verification to make sure the data isn't corrupt. It would be nice if there were additional checks in the Zwave specification, but there aren't. Its on you to make sure you're choosing the correct firmware image to flash for each particular device.
I also wouldn't expect Inovelli to replace a device that you damaged. Warranties are to cover manufacturing defects, not accidents.