Hello Jeff,
If you specify login credentials for a host, TestComplete will open a new remote session when executing a task. Currently, the screen size of the RDP window that opens cannot be changed and it looks like it is too small for your tested application.
To resolve the issue, do not specify login credentials for the Network Suite hosts - in this case TestComplete will not open a new session on the remote PC, it will run the test in the existing user session. So, you can open an RDP session yourself and TestComplete will use it.
In TestComplete 8, this behavior will be improved - the screen resolution of the RDP window will be equal to the screen resolution of the Master PC, so you can set the resolution suitable for your test execution.