Dingoonity.org

Regarding the firmware - the instructions are literally in the OP of the thread you saw.

You'll also need to re-root your device. This is done by: (Taken from: http://www.freaktab.com/showthread.php?6014-How-To-easily-root-CX-919-%28should-work-for-all-rk3188-devices%29-full-rooting-package)
Download http://www.share-online.biz/dl/54FMSCQM0U
Replace the RootExplorer.apk with an updated one, and same with SuperSU.apk.

Now, follow these steps:
1. On the device, enter settings, developer options, and enable USB debugging.
2. Connect the device to to your computer via USB.
3. MAKE SURE YOU HAVE ENOUGH BATTERY FOR A 10 MINUTE OPERATION. If the device shuts off in the middle of the process, you might need to reinstall the firmware.
4. Run TPSparkyRoot.bat and follow the on screen instructions.

Your device is supposed to reboot 3 times in the process. In the end, you'll have a rooted device with Root Explorer and SuperSU.
Also, install another launcher. There's a problem with the original firmware, in which the homepage is loaded solely with icons from \mnt\sdcard\apks\, meaning anything else you put on there will be removed by the next reboot.

You'd also want to install SetCPU and Tincore, for improved CPU control and better keymapping.

That's basically it. Enjoy your new JXD S7800B.

Ya I recommend nova launcher much better then default launcher and no missing icons, I read the mising icons happens on a lot of android devices with default launcher though.

what about emulators anything to add or remove from the stock emu?

Mine did'nt have many apps per-installed.. they do have a folder full of apk's and when you first click it'll ask you if you want to install.. I ended up deleting all the APK's (backed up to computer)
I did try a few of the emulators on it, most of them are just standard emulators you can get of play store or otherwise, nothing special most of them are reasonably up to date also maybe 6months old?

One in particular you'll be interested in keeping is probably epsxe, that's actually a premium app, I don't know if JXD hacked it or what but if you go thru play store it's like 4-5 bucks. (1.9.5, current is 1.9.12)

I also kept fruit ninja, the JXD copy seems to be hacked so you can use all the settings and stuff.. FN is free but costs to unlock everything.

and I also kept Expendable Rearmed, Not sure if that's a free game or what but I thought it was pretty good kinda reminds me of smash tv (the controls anyway), it uses both analog sticks so it's a good game to try them out.

yes it uses them natively, It was the 2nd app I ran after fruit ninja (I play FN on Iphone) so it was the first thing I ran then I ran that expendables cause it was the only other game that came with the unit that I thought I might like.

I didn't set up a thing it was all setup and ready to go, It should have been on your launcher lcick it and it will ask you to install..

The apk's for the apps on your launcher are stored in a folder marked 'apks' you'll see a list like 3_3, 4_2, etc
There are apps in there skype, facebook, fruit ninja, etc ,etc

It's safe to delete the apk's if you don't want them, I removed htem to save room but I kept epsxe/fruit ninja/rearmed.

the emulators I did not have on my launcher or app tray.
I found them with explorer..

Emulator APK's are stored in a folder labeled "Xiaoji" there are a number of emulators in there.. also safe to delete if you don't want, if you want them just click on the apk and it will install.

there are also a few roms in a folder named "games"
only 1 or 2 per system, some had none (ex: PS1 just had it's bios' no iso)
there was a psp game "Darious Burst".. Donkey Kong 3 for SNES, Etc , Etc

All together it's about 1gb of files.