Can't update/calibrate N64 Mod Kit/HE Joystick

I'm having issues getting Ultimate V2 to recognize the N64 Mod Kit/HE Joystick properly.

- When (using the supplied A to C cable) plugging in computer to rumble pack, Ultimate does not recognize the Mod Kit/Joystick.

- When holding L+R+Start and plugging in computer to rumble pack, Ultimate recognizes it as the NGC Mod Kit, not the N64 Mod kit. It allows me to update firmware here, but if I do the rumble pack just rumbles constantly, even when not connected to the computer. The only way to stop the rumble is to remove the pak from the controller, but when I put it back in the rumble resumes. It does not give me the option to calibrate the stick.

I am, however, able to use the 8bitdo Firmware tool which let me install 1.01. I did see, though, that that changed it from 1.03 to 1.01 - I do not see an option to go back to 1.03 (if that was truly what it was shipped with). With this I was able to stop the constant rumbling.

FWIW I am able to pair the controller with the Analogue3d and it does appear to function fully, but I feel like Ultimate V2 should be recognizing it as the N64 Mod Kit and I should be able to update and calibrate the stick here, like I can with the 8bitdo N64 controllers - that doesn't seem to be the case for me.

Any thoughts or shared experiences are appreciated.