Hi,
When you export your TC test to QAComplete from TestComplete UI, the target test project suite is attached to the corresponding QAC Automation as a zip archive and the test run mode is always set to 'Copy the test project to and run it in a temporary folder'. Having this setup, all the changes you make on the TC side will not influence the originally created QAC auto test (the previously attached archive remains the same). For this approach, you are totally right: to update a TC test on the QAC side, you'll need to import the modified TC project one more time and create another auto test in QAC.
However, if you create your auto test directly from QAC UI, you can select the 'Run the test project in place (if possible)' run mode. In this case, you'll need to have the latest TC project version to the target host, and it will be started by the Test Agent from the folder you specify in the automation settings. This can be a more reliable approach, specifically in case you usually modify the TC project directly on the test host.
Please refer to the Assigning TestComplete Tests to Tests help topic for more information.
