Presumably not. Unless the developer cares to document the internal data types and syntax of its otherwise oaque data blob in custom controls, there is no way to access this stuff. Chances are there is some internal spec, as Lumetri is used across different programs, but I haven't seen anything public. Then again even if there is some documentation, it may only be accessible via the C++ APIs. Anyway, the answer is 99.9 % "No", I would say.