[G Tablet Q&A, Help & Troubleshooting] TJEvans:
NVFlash is never needed to flash a rom. It's a tool typically used to recover from a "softbrick." It CAN be used to flash a rom, but there are much safer alternatives. In fact, NVFlash is considered to BE the alternative to the regular methods.

starting with 4349, 1.2 bootlaoder, you can use the stock recovery to flash just about any of the 1.2 roms.

Which Rom are you interested in? The only roms that do not have a 1.2 equal are the gingerbread type roms. For instance, if you wanted Vegan 5.1.1, then Brilliant Corners is the 1.2 alternative. That's what I'm running. It's got to be one of, if not THEE, most complete rom available right now.

most 1.2 rom information is located at Slatedroid, not here.

I suggest that you check out the new website created by a user here (GoodIntentions). It's a "G-Tablet for Dummies" website. It contains a ton of useful information for beginners like yourself.

There IS a CWM that is specific to the 1.2 bootloader, but becuase the recovery on stock 1.2 has more options than the stock recovery used on 1.1 bootloader, it's not absolutely necessary. It's a good tool to have, but not necessary.

Your basic flashign technique for a 1.2 rom is as follows...download the .rar file the coincides with the rom you want. Unzip it to the root of your G-Tablet's memory. Restart the G-Tablet while holding down the volume up key. The tablet will boot into the stock recovery, and use the files you unzipped to flash the new rom. The rar file will contain to objects, a file called update.zip, and a recovery folder with a "command" file in it. What will happen when booting into recovery is that the tablet will first check to see if there is a recovery folder present. Think of this as a PC checking the floppy drive for a boot image before booting from the hard disk. If it sees the recovery folder, it will, by default, run the command file within it. The command file will unpack and install (flash) the rom image from the update.zip file.

With most of his roms, Roebeet has included the 1.2 CWM image in the package. It will not install automatically. There are threads available (on slatedroid) that contain instructions on how to activate the 1.2 CWM. There are various methods, if one doesn't work the first time.

If you are dead set on flashing a 1.1 rom, you'll first need to downgrade back to firmware 3588, which is a 1.1 bootloader firmware. Gojimi has posted instructions on XDA on how that is done.

So, your first step, is research the roms on XDA, Slatedroid, and other Android Tablet forums to find which one would best suit your needs.

As a beginner, I highly suggest that you steer away from the honeycomb roms, as they are still in alpha status and mainly used for testing and troubleshooting. In other words, they won't work perfectly, so to save yourself headaches, wait until your more comfortable with a more polished rom. ALL HC ROMS ARE 1.2 BOOTLOADER ROMS

The gingerbread roms are pretty stable, and from what I hear, pretty fast, but they lack a few things, namely full hardware acceleration. At the same time, if your heart is set on streaming netflix movies, then these might be the best choice for you. THE MOST POPULAR GB ROMS ARE 1.1 BOOTLOADER ROMS

The Froyo roms, while the most prehistoric are the most stable, most complete, and less "buggy" of all the roms. There are many varieties, based on various tablet user interfaces. FROYO ROMS CAN BE EITHER 1.1 OR 1.2 BOOTLOADER ROMS...BUT, the 1.2 branch has more of them, and there are 1.2 equalivents to just about all of them, so sticking with 1.2 for a Froyo rom is the best option because you'll still have the advanced stock recovery if you decide to stick with it.

That being said...why not mess around with the stock 4349 firmware to get a feel for the tablet a bit more? Check some things out. Get Titanium Backup and practice a bit with backup up apps and restoring them (you'll use this a LOT, especially if you rom jump trying to find the best one for you). Find out what you want the tablet to do, based on the stock firmware limitations. Some people are still using stock and not finding it too horrible. Spend a week with it, see what else you want it to do, and ask again when you know what you want out of your G-Tablet. And above all, ENJOY...you just entered a whole new world of personal computing...don't rush into anything and end up regretting your purchase.

P.S...I highly recommend you check out "G-Tablet for Dummies"