Cartridge too light for counterweight?

I just purchased a Pro-ject 6 Perspex, and finally managed to get it up and running (no thanks to the horrible manual).

It came with two counterweights, the lightest one rated for 8-~ gram cartridges. The cartridge I got (Audio Technica AT33EV) only weighed 6.9 grams, but I was still able to balance the arm out with the light counterweight, and then had no problems dialing in 20 on the downforce scale (cart says 2.0g for recommended downforce).

After completing all the adjustments, I noticed a small bag containing a small weight (that I measured at 2 grams). It will fit over (or under) the cartridge mounting point on the arm.

Is there any point in adding this to bring the weight up, or is this just for cases where it is impossible to attain balance and then dial in the proper downforce using the supplied counterweights.
If you have acheived the correct settings, and it sounds as if you have. Don't add any more weight at the cartridge end tha necessary. The least amount of mass is best for tracking. Also make sure with the weights at the cart end that you accomadated the VTA for the extra mounting height.
I will be curious to see how you like your new table. I have looked at the RM10 but still ahven't decided to trade out of my current table yet.
Actually, it's always best to keep the counterweight as close to the pivot point as possible. If it's really far back on the end stub, you might want to add the extra 2 grams at the cartridge end. If the counterweight is half or more in, I'd just leave it.
It sounds fine to me, but its my first turntable and the only reference I have is various shop setups I've heard. The counterweight is quite close to the pivot point, so I guess that is ok too. Wouldn't adding the extra weight push the counterweight further back rather than forward?

Also, I'm not sure what "Also make sure with the weights at the cart end that you accomadated the VTA for the extra mounting height." means.

I'm sure I will start to obsess about how it could be better in time, but for now I'm satisfied. I don't have my regular CD player, a Wadia 850, hooked up yet (I have moved, so it is in a different continent :) So, for comparison I only have an ipod with a Wadia dock set up using the analog output. If the turntable weren't able to beat the ipod's DAC I would have demanded an immediate refund :)
Ahochan, sorry, I read your post wrong. You are correct with adding the extra weight, it would indeed move the counterweight back not forward.

"Also make sure with the weights at the cart end that you accomadated the VTA for the extra mounting height."

This means if you did use the 2 gram weight it goes between the cartridge and headshell and would add some height difference that would need to be adjusted at the arm base, (VTA).

Sounds like you are up and running very well.
In addition to MoFi's reply and to answer your question. VTA is Vertical Tracking Angle which is the relation of the centerline of the stylus to the groove plane. You can do a little research and experimentaion for your particular situation. But in short the angle can either enhance or muddy the bass line and at the same time effect the rest of the bandwidth. I have always felt that getting the bass as tight and acurate was the first priority. The rest falls into place. But fo now let your cartridge break in before you agonize over it too much.
Changing weight at the cart will change the effective mass of the whole arm/cart assembly and as a result, will change the resonance frequency as well. So the best way to determine if more weights are needed is to run through resonance test, both lateral and vertical, using a test record like the Hi-Fi News Analogue Test LP.
About the "Hi-Fi News Analogue Test LP." The description says it comes with an alignment protractor. Is this just a simple paper one, or a more fancy one?

Does anybody have experience with this for a pro-ject table:
Ahochan, that protractor is just a round cardboard. I wouldn't trust it.