Hi MindFlare and welcome to the forum! You have this issue because you forgot something! You forgot to write-protect your controller. The last 6.8x version will check for CP0 bit of the PIC18F87J50 controller from your TL866 and if found unset will disable the bootmode (hence that reset error) and block the device by spitting out that funny data block that you see.
In fact that funny data block was everything i needed to do my analysis! This 80bytes block it's the internal decrypted serial number data block (this block is stored in an encrypted format internally at the 0x1FD00 address). When the firmware detects the CP0 bit unset then will spit out this block instead of normal data. I don't know if this is by design (for debug purpose) or a firmware bug.
Anyway this block is ok. This serial numberblock has a cyclic redundancy check (CRC16) inserted at the end of the block (the last two bytes 31 45) of the first 78 bytes and a simple 8 bit checksum of all bytes from offset 5 to 33:
39 38 34 39 46 38 37 36 34 33 42 30 32 39 37 35 45 41 46 41 39 32 35 39 33 32 32 01 36
The 8bit checksum of those bytes is 0x2D which is inserted at the offset 34.
The device code and serial number are ok as well.
You must force the boot mode again with that resistor, which btw there's no need to solder it; just keep the resistor leads still at the indicated points while inserting the usb cable. Once the programmer has entered boot mode remove the resistor (keep the firmware updater open to see if the programmer is entering boot mode).
After that you must tick the code protection bit and click the write button next to it (see the attached image). This will set the CP0 bit of the PIC from the programmer. Of course in your case select the A bootloader and click the write button next to this option to change to A version.
Finally close this advanced window, select A firmware from the main window and click reflash to flash the normal firmware version. That's all! good luck and please report back!