30% Cool Power is fine, in fact the higher nitro will make tuning easier. What you are describing is far from normal and given the age of the engine (I know you said its new but it has not been produced in while) you may have to clean out the regulator if it was stored with any oil or fuel in it.

BUT...Let us start at the beginning and work our way through this.

1) You are using a YS check valve and it is installed properly correct?
2) The tank is holding pressure correct?
3) You put a new YS #4 or OS Type F plug in the engine.
4) Flush the regulator
5) Take the HS needle out and crank the engine over at full throttle WITHOUT the glow driver to flush out the needle passage.

The LS needle is just an air bleed and further CCW you turn it the leaner you are making the idle.

GIve the above a try and report back. That surging is typical of a lean condition and I suspect there is just something that just needs flushed out of the passages in the engine.

Pete