I don't implement macros within Excel, so I can't give you any help with that.
Regarding using the OTA API to upload the data yourself - there are many examples of code within the documentation. Have you studied those?
Basically, what you will need to do is.
1. Create folder(s) in the Test Plan area.
2. Create each Test Case
3. Add Design Steps to the Test Cases you create.
Look at the documentation for information on SubjectNodes and TreeManager (for the folders), the Test object (for the test case) and the Design Step object. There is an example associated with the Test object titled "create a test and change some properties". That will give you hints on how to create the folder and the test case.
Regarding using the OTA API to upload the data yourself - there are many examples of code within the documentation. Have you studied those?
Basically, what you will need to do is.
1. Create folder(s) in the Test Plan area.
2. Create each Test Case
3. Add Design Steps to the Test Cases you create.
Look at the documentation for information on SubjectNodes and TreeManager (for the folders), the Test object (for the test case) and the Design Step object. There is an example associated with the Test object titled "create a test and change some properties". That will give you hints on how to create the folder and the test case.