aerenderer is a background application. You render files by opening After Effects, opening a project, adding a composition to the render cue. What are you trying to do with AERenderer?
I have just purchased The Foundry's Cameratracker (which is excellent by the way) and also two versions of Cameratracker's Render to put on my two rendering machines. The render versions need to run in the background and not launch GUI and I was told by The Foundry to use aerernder to do this, but having never used it before I have struggled to get started.
I haven't used this plug-in yet. The Foundry will be better able to help you than I will. aerenderer is a command line app that is accessable to scripting. Run it on a Mac with Lion and you get a terminal window that pops up with instructions. Here's an excerpt:
1] aerender renders After Effects comps. The render may be performed either
by an already running instance of AE or by a newly invoked instance. By
default, aerender will invoke a new instance of AE, even if one is
already running. To change this, see the "-reuse" flag below.
2] aerender takes a series of optional arguments.
Some are single flags, like "-reuse". Some come in flag-argument
pairs, like "-project project_path". And one comes in a triplet,
-mem_usage image_cache_percent max_mem_percent.
3] aerender with 0 arguments, or with any argument equaling "-help"
or "-h", prints this usage message.
4] The arguments are:
"-h" print this usage message
"-help" print this usage message
"-reuse" use this flag if you want to try and reuse
an already running instance of AE to perform the
render. By default, aerender will launch a new
instance of After Effects, even if one is already
running. But, if AE is already running, and the
"-reuse" flag is provided, then aerender will
ask the already running instance of AE to perform
That tells me how to run aerenderer from the terminal (on a Mac). There are similar things to do on a PC but it's been so long that I've messed with the inner working of a Windows machine so I can't remember the exact procedure. I can't imagine that the Foundry would want you to run this from a command line.
I'd check with them. I'm sure you know they have an extensive Camera Tracker training series on their site.