So Finally today I stumbled upon a solution posted in slatedroid by Micky.
Instead of flashing the Viewsonic ROM to start with, we need to flash this ROM instead.
After you download the ROM from the link above, search for the TeamDRH CWM 18.104.22.168 and download. Extract the RAR file and replace the recovery.img in the folder with the TeamDRH CWM, cuz the one in the ROM is too old and doesn't support the latest ROMs.
[Note: If you want a larger system partition, follow this.
Open the file flash.cfg and find this no. 209715200 and replace it with this no.419430400
Now when you flash this ROM, you will get a system partition of 400MB.
If you use this method, you don't need to delete any system files after install from the ROM.]
Reboot the tab to CWM and wipe data/factory reset and wipe dalvik cache. Twice.
Shutdown and reboot to APX mode and connect to PC
NV Flash the ROM, let it boot and then shutdown.
Now to flash Jelly Bean.
Download Smoother Bean by nobe1976
Then boot the tablet to CWM
Again wipe data/factory reset and wipe dalvik cache. Twice just to be sure.
Flash the Smoother Bean zip file
Do not wipe data/factory reset or wipe dalvik cache this time.
Let it boot and run for a few minutes.
[Optional: Now install an app from play store to delete system apps and also a keyboard, Swipe or as such.
Open the system app remover and uninstall Gmail and AOSP Keyboard.
A few more apps can also be uninstalled, such as wallpapers, DSP Manager, Music FX, but not all.
Before deleting the AOKP Keyboard, you can copy it from the system folder if you want the stock keyboard. LatinIME.apk file.
(This does not apply if you modify the flash.cfg for larger system partition)
We need to uninstall these apps cuz after flashing with the above ROM, the system partition is only 209MB, so after flashing JB, we get around 5-6 MB free in the system partition. After uninstalling the apps, we get around 34 MB free.]
Hats off to nobe1976. He is able to develop a JB ROM that can be installed in a 200 MB system partition.
Well after everything, I hope whoever tried this in their MALATA Zpad is able to see full 1GB RAM, or around 850 MB approx.
[After this succesfull experiment, I would like to request a developer to kindly help us modify the system partition of the above ROM to 350 MB or more if possible.
Its a small request from us Zpad users.
(Note: From the help of all the users, I have been able to increase the system partitiom to 400MB)]
If anyone could help, I will be gratefull, we all will be very gratefull.
This is really pushing the limit.
Edit: Now you can use 1GB RAM present in your tablet and all the space available in the flash memory.
Note: This method can be used in all variants of the Zpad which has 1GB RAM and 16GB ROM.
Note: This tablet is sold by different names all over the world. The one I use is HCL AP10-A1