Are any other ranges working?

These are two different but frequent features of Stripchat. Briefly on the points:
1. Vibration is not available in the 55-75 range: This is a limitation of the Stripchat platform itself. Most likely, you will not be able to assign a vibration to one specific tip size in this interval. Solution: Try assigning an action to an interval (for example, 55-75 or 50-80), rather than a fixed amount. The interval settings are located in the same place where you set up tip reactions.
2. The control panel is visible only to the donator: This is the standard privacy policy of Stripchat (as on many other sites). The platform intentionally shows vibration control buttons only to the viewer who has paid for a private session or sent a tip with access to the control. This element is not displayed for other chat rooms. This cannot be changed in the settings.
Bottom line: The first problem can be circumvented by adjusting the intervals. The second is not a problem, but a feature that protects the privacy and value of the donation.