New A5 issues

Ok, so I finally get a chance to take my new A5 (to me) to the field and play. Inevitably I had some issues. Here is the setup:

A5/e-grip

Rap4 M4 style stock

Palmers QEV/larger lines

CO2/remote/palmers stabilizer

Flatline

First up, when I get up to chrono the marker, which worked fine a week before at home, I followed the Palmers instructions and set the marker at 315 with the bottle directly on and than put the remote and stab on and used it to get the FPS down. Problem is to get the FPS down to a reasonable level, the PSI was in the 600 range and the cyclone would quit feeding. After getting frustrated, I took the remote and everything off and run with tank on the gun. Later, I took the stab off and just ran the remote. Seemed to work better. In hindsight, I am thinking I should have just set the Stab at 800ps or so and used the FVA to get the FPS down. Not always thinking clearly when the kid at the chrono is sitting there tapping his toe at me and offering little or no help. Next time, should I do what I explained? Does that make sense?

Secondish issue. Once I got the FPS and the Cylone working, (without the stab) I tried some 3 shot burst and what I basically got was two semi auto shots, and then the thing would go full auto for a couple of seconds and throw all kinds of paint. Eventually, it would recock. Later, it stopped recocking and I would have to stop it by grabbing the handle. When I switchi it to semi auto, it was fine. One shot, one cycle, not matter how fast I pulled, it was fine. I never got this worked out, but started thinking. When I took the factory plug off the back and went to intall the stock, I realized the stock did not come with an Oring to keep the bolt from banging the back of the marker. I compared the original and realized it has a different system than I am used to on the 98. The stock A5 plug has a "piston" type system, and on the new stock, it doesnt have it. I didnt want damage to occur to the bolt, so I put a gray oring from a small parts kit to cushion it. Should I have done this? Is the oring keeping the sear from catching? Since the stock is plastic is this enough to cushion?

At one point, I took off the QEV and put the stock fittings back on and just in case, I did have full tanks and I put a new batter in. I will say that the marker seemed to work better when I put the full tank on. The issue did seem to get worse after a hopper of balls.

Help me Obi Wan, you're my only hope.

Stock plug that I took out has a "plate" and the grey oring fits behind that. If you take the oring out, you can actually push the plate back. I guess more like a spring than a piston? Anyways, I was just comparing the two and did a spring hole depth check. I noticed that even with the oring on the Rap4 stock, the depth is considerably deeper than the stock end cap. I assume this could be an issue? Do I need to add a BB or put in a longer spring? Pic below has my thumb marking where the depth on the spring hole in the Rap4 stock is vs the stock end cap.

Also, the e-grip I have has semi, 3 shot burst, full auto and two others. Once you set the mode, you have to pull three times and than the mode kicks in. I had it set on 3 shot burst and the first two shots would be semi auto as normal and on the third is when it would go full auto.

Regarding the stabilizer, all these issues were happening even once the stabilizer was taken off. I am kind of lost as to the no stabilizer thing as it seems like everyone says how great these are and how they are recommended instead of an expansion chamber.