i dont find the manager source package file or manager.aip file for rebranding purposes. Is the feature closed?
Please do not send private messages with questions about the program. That reduces your chances of getting answers. I have moved your question to the public forum.
The Guide on how to rebrand for Windows was removed in October 2019. It was obsolete, because packaging and distribution of the program changed. I don’t know whether you could still rebrand it or not, but there is no guidance on how to do it.