The device IS a modem*. It's not a ROUTER. It does not support ethernet.
*Well it doesn't really modulate and demodulate, but you know what I mean.
So far we know that the bandwidth limiting factor is done by the device that they register on their network before handing it to you.
So in theory: If they provided a removable RUIM (SIM) with their device (which they don't). The reason why I think they prevent us from buying our own devices has maybe got something to do with what I'm about to say. Example if you buy a Lite Package they give you a phone that is not able to connect to EV-DO (3rd generation speed equivalent) network. So by buying your own handset that is EV-DO capable and plugging in your Neotel RUIM, will then allow you to browse at higher speeds but at the NeoConnect Lite package pricing rate. So that is my theory to why they don't want us to buy 3rd party phones

And the fact that they are the only CDMA 2000 network in this country. (They use that also) And the reason why there is no RUIM to remove, hence they can milk us more for where on MTN/Vodacom we pay for the data used not the bandwidth (how fast, except maybe for Vodacom that wants to add more charges on HSDPA).
We also know that they hand out you a public IP address. Why the others claim that nobody can connect to them is mind boggling, because Neotel claims no shaping, no capping, no firewalling. So in theory people should connect to you directly. You should check your own firewall settings.
Using it as a modem on a Linux box, should work, as long as the device supports Abstract Control Model (USB CDC ACM)
modprobe acm
That should create a device under /dev/ttyACMx
Your dial number is #777
The procedure is very similar to using a gsm type phone (like nokia) on linux, except for the dialing number being *99#
What I don't know is if there is a pin, now I would guess you either remove the pin from the phone with the windows software. Or you can authenticate to the modem every time before you dial with the pin code.
Just google CDMA and linux dialup and you will see there are plenty of people got it to work in one way or the other.
The NeoConnect Lite package doesn't make any sense at that price you only get "gprs/edge" type performance, no where near 3G.
Have a look at the device they give for the NeoConnect Lite users:
Huawei :ETS2258 This only encourages my theory further. The NeoConnect Prime device should be different and should be able to connect to the EV-DO network.