check your o-rings and that everything is tightened down but dont torque it too much

Well if you got a 98C when you tapped the hole on the rear right reciever.. did you try to make sure that there is nothing at all cming off the sides.. I mean like a jagged edge or something. My friend installed his and there was a small jagged edge where he tapped the hole out and it was created a gap between the air hose and rt inner connection hose... Make sure that they are completly touching.. there should be little or no play in the adjustment connector if you are moving it left to right or any direction.

If that is not the problem.. Make sure that your co2 is full..make sure velocity isnt high.

Now that that is checked, remove barrel, squirt about 2 small drops of oil into your tank adapter. Cock it back, put on co2, and fire like 10-15 times. This will oil up the interneals, and send some oil through that line, which could help to seal the connection..

If it still isnt working. Turn the RT adjustment screw all the way into  the gun. Then while firing, on ever 2 shots, make a small turn out with the rt adjustment screw. This will eventually find the sweet spot, and get your rt the amount of air that it needs to run with.  "sweet spot" would be a continuous strand of full auto.. Also, do not press tirgger super hard. Ive heard that too much force can stop the air from pushing out, and all it will do is reset the trigger back to its place without you letting it go.. which is pointless..
  A light touch of the trigger, just enough to make it fire is good enough to set it off..

and..If the RT still isnt working.. only thing that i can suggest if take it to a pro shop or something near you to have them look at it.

Hope this helps a little...

yes it should keep firing..

The thing is.. if it is firing semi auto.. then its not working.. so like i stated above, there has to be a leak.

With any RT, there is no way for you to ajust the screw in and out, while firing and it does nothing unless there is a leak, or somethingis not properly sealed, or the number 1 cause, is not enough co2.

Get the co2 refilled, and try it. It worked flawlessly with installing mine, and 2 friends of mine (when done right..)

Also, take out the screw that connects to the outside right area of the power tube and mark it on each side where the hole is in it. (with a permanent sharpy or something..) and turn it in, when all the way in, without overtightening to break the power tube.. The lines should be aligned with the outter micro line which is connected with the air flow adjuster...

I hope this helps a little more. Check the connections, velocity and air, hope you get it working like the rt should soon.

and you still havent said if you got a A-5 or 98C

well i have the RT in my a5 ,and everytime i take off the grip/trigger section and put it back on i break the seal from the trigger to the rest of the marker .its a little black o ring seal on the cylinder inside the grip .you should have a lok at this as all it takes is for a tiny little peice of that seal to be shaved off .try reinstaling the grip but this time loosen all screws in the grip so you dont have to force it on and be very carefull ,

worth a try .