1) Download the zip file attached to this post to a folder on your PC and unzip it. Find "Superuser.apk"and download it to the same folder (it is too large for me to attach here - even zipped up). It was posted earlier in this thread or you can probably find it elsewhere, as well.
2) Connect your tablet to the same PC and enable USB storage on the tablet.
3) Copy the files "su", "Superuser.apk", and "init-pppd.sh" to the the NEXT8P12 drive. This will put them in the root directory of the internal flash of your tablet ("/sdcard").
4) From the toolbar on your PC, click "Safely Remove Hardware and Eject Media". When the dialog appears, click "Eject Android". You should get a popup message from the PC when it is "Safe to Remove Hardware".
5) Turn off USB storage on your tablet, disconnect it from your PC, and remove the USB data transfer cable.
6) Using ASTRO, navigate to the "/sdcard" folder. Copy the file "init-pppd.sh" (shows up as "init-pppd") and paste it in the "external_sd" directory. This will save your original file so you can restore it easily later should you want to do so.
7) Copy the modified "init-pppd.sh" file from the "/sdcard" directory (from step 3, above), navigate back to the "/etc" directory, and paste over the original "init-pppd.sh" file. Leave the filename the same. You will be asked if you want to overwrite the original file - click "Yes".
8) Install an active SIM card into your 3G dongle (I used a Huawei E220) and connect it via an OTG USB to micro USB adapter to your tablet. The LED on the dongle should begin to flash in short order. I tried this several times without a SIM card installed and it did not work for me.
9) Within a few seconds, you should see a new annunciator in the status bar in the lower right corner of your tablet's screen, where the time is displayed, between the WiFi and Battery annunciators. It looks like the one on your smart phone, with the familiar stepped bars. It will probably have an "X" at the bottom, for now - this is normal.
10) Open up "Settings" on your tablet. Press the "More..." button under the "WIRELESS & NETWORKS" heading. You should see two choices: "VPN" and "Proxy settings". Leave everything connected and set the tablet aside for 5 minutes. When you come back, the annunciator in the status bar shoud show that you are connected. You should now see an additional choice in the settings window: "Mobile networks". If you don't see this, press the "WiFi" button and then press "More..." again.
If it's still not there, give it a little more time... be patient! I thought it took a lot longer on the first tablet I did (like 10-15 minutes), but my wife's tablet only took 2-3 minutes to set up the 3G connection.
You may have to disable your display timeout ("Sleep" set to "Never timeout") for this to work properly, I'm not sure. I disabled it on my wife's tablet, but I was using my tablet when I rooted mine so the display did not shut off.
11) If you get this far, pppd has started on your tablet and your modified "init-pppd.sh" script has run. If you did everything right, your tablet is now rooted. Look in the "/system/bin" directory and you should find "su", and you should find "Superuser.apk" in your "/system/app" directory. You can delete the files you copied to the "/sdcard" folder in step 3 and restore the original "init-pppd.sh" file that you backed up to the external SD card to its original place in the "/etc" directory.
Note: I started this procedure from memory, then updated as I attempted to root my wife's tablet. It should work. If it doesn't, check your work and try again.