The drill for the VKB sticks is only slightly convoluted. First, you should have the latest version of the config, bootloader and latest correct FW for your stick as well as everything else VKB in a single folder. From the configurator press the bootloader button. Flash to the current FW. Once that finishes and you're back at the configurator, press the default button in the configurator(important--don't skip this), then start calibrate--operate all axii then click stop calibration. The stick will re-start. That should do it. Sounds like you've skipped something if the axis is registering.
There's probably a video about it on their YT channel how to do it. I don't have the gladiator or their new throttle and other stuff but I believe you can only flash with one thing connected at a time.
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