You said "I tell stairs to go to rear of plane". If you mean you used the "Operate Stairs" commands, that's the only thing that commands does: operates the stairs and nothing else. It doesn't board or deboard anything, it just *moves* the stairs.
To see any passengers, you should give a Boarding or Deboarding command, which will operates stairs automatically, call a Passenger Bus, which will arrive to either bring passengers to the plane or take them out.
This, on a parking on the Apron, in which a Bus is required. If your parking has a Jetway, instead, in order to see passengers, the Jetway MUST be made with SODE, passengers cannot use a default jetway or a 3rd party jetway that uses the default (CTRL+J) system.
Which is why, the biggest feature of GSX L2, other than passengers, is the fact that has replaced all default jetways at all default airports with its own SODE jetways, which will of course work with passengers. On 3rd party airports that use SODE jetways, passengers will also work.
This leaves 3rd party airports that don't use SODE jetways. We don't touch these, so by default passengers won't be seen but, another big part of GSX L2, is the ability to replace jetways at 3rd party airport that still doesn't support SODE, with GSX own, using a procedure of first excluding the original jetways, and then adding the GSX models, this of course is explained in the manual, and there are a couple of video tutorial in this same section of the forum:
http://www.fsdreamteam.com/forum/index.php/topic,18372.0.htmlhttp://www.fsdreamteam.com/forum/index.php/topic,19171.0.html