Now to me the car feels slightly poorly mapped, if you know what i mean? a bit lumpy and the boost just comes in in a big lump..

Pumagreed, what can I say?

Today I have ordered a blueflame cat back system,

Decent enough, make nice Manifold's as well. But Milltek exhausts are just sex

What are the advantages of running the actuator pipe direct. (and do i have to leave the amal valve plugged in or unplug it)?

Leave the solenoid (amal) plugged into the electrical connector, this stops the engine management light from coming on the dash. Otherwise, nothing else needs to be connected to it. The difference in running a Forge actuator or a VERY good map is unbelievable. Setup the same as you would on an RS Turbo, straight from actuator to compressor. Wind the actuator arm fully before fitting, then turn opposit direction 2x 360 degree turns. This will give you a good basis to start with adjusting boost, but you must have a proper boost gauge installed to keep an eye on that rising pressure. Much more responsive and controllable drive, not so erratic.

Is it worth buying the forge actuator with blue spring?

Straight to compressor, yes the blue spring.

should I have it remaped again? or buy something like dreamscience?

Taking the solenoid out of the loop, means the fueling is no longer controlled as efficiently. So to have a actuator setup, you need a decent remap like Bluefin or better still, dreamscience, Unichip etc. to pump enough fuel in to compensate.

what boost (roughly) should it be running?

GT2560 21psi max, a lot push them further, but if you're planning on nailing it around frequently, set the actuator to peak 21 and it'll drop and hold at 19psi....DO NOT fit a bleed valve or anything silly to the actuator hose like a tuning company in this country did to so many FRS'

Hope that helps