How can I specify the Activity ID in a Tin Can Captivate Course?

Hello,

I am currently creating an LMS in which it hosts Tin Can courses. We have our course developers who send me Tin Can packages/courses produced from Captivate, and I host it on our LMS by appending URL parameters to the launch URL such as the LRS endpoint url and the actor. However, I can't seem to tell the Captivate package what activity ID to send to the LRS. It keeps sending activity ID: http://Course_ID1/Slide_5, even when I added "?activity_id=http://example.com". How can I tell the package what activity ID to send to the LRS? I can tell it the LRS endpoint and the actor object, but I can't tell it the activity for some reason. It keeps setting the activity ID to http://Course_ID1/