There have been some backwards compatibility issues with TDAbleton 2.6.4, which was released with build 2025.31740. Improper max device loading can occur if you are opening an old Live Set with TDAbleton rack devices. Also if you create new rack devices, they will likely have a problem with the fixed version in a coming release.
I recommend all TDAbleton users put this patch in just in case, until next release.
Replace the TDA Project folder in your TouchDesigner Remote Script with the one in this archive:
TDA Project.zip (45.9 KB)
Your remote script folder can be found using the MIDI Remote Script Folder parameter on the TDAbleton component Utilities page, or via the Live browser → TouchDesigner folder in your User folders.