The ESC is still fully programmable and works with 100% functionality on the Castle Link. This pop-up is simply informing you that firmware updates are disabled for the Talon HV120. This is because it is a new product line and there is currently only one firmware version available, hence, no updates.
Since you cannot select a different firmware version, the firmware update option has been temporarily disabled. However, when a new version of firmware is released for the Talon HV120, this notification will disappear.
We are currently working on adapting firmware version 4.20 to the Talon HV120. Version 4.20 is the same version current available for the Phoenix Edge and Phoenix Edge HV series ESCs. Once it is available, this update will allow the Talon HV120 to work on high pole count, high inductance out runner motors like the newer Hacker 28-pole out runners.