Two points- When a spool is in the top chamber, the initial question about the thin film gearing, and you use the winding lever, the silver gear may not move. Put a little pressure on the spool end above the gear while winding and see if the gear starts rolling. Ideally it will roll with some pressing on the spool. If it rolls without any pressure, all is fine.
I mention this becasue it is possible for this axle to be set such that there is no registration of film movement at the beginning of the roll, sometimes into the first or second frame. But eventually the film and paper should add enough diameter tot he spool to start it rolling, and having the frame counter start moving. Very rare condition, but just to mention it.
Second point- you can test the film sensor in one aspect of function by putting an index card, maybe doubled over, in between the two roller. Just building up thickness. Now move the black 'foot' that Flighter points to forward. In doing this, you might hear a clunk from inside the camera on the wind side. Move the foot (some pressure is fine, end of travel will be obvious) both with and without the index cards in between the rollers. Without material, no clunk, with material, clunk. Not super loud but can be heard.
The clunk is the film sensor releasing, engaging the film metering and counter system.
If it releases/clunks, then the overall system is functioning. And now Mr Bill's point about film thickness adjustment comes into play. The adjustment is under the panel, a somewhat tricky thing to get to and to adjust. Nothing horribly complex but a few layers of fiddly parts to get into.
A possible cheat is to 'preload' the film thickness sensor by putting a thin tape on the top roller. A one (or two- try one first) layer of cellophane tape might do it- no overlap on the layer. We are dealiing with 1/10mm here. Prepare to use a test roll, or to keep unloading the film in a darkroom, to check this out. It's a hack that might work to trip the counter system with actual film in the camera.