As said about taking to tuner and ditching the in car boost controller you would be far better off with the standard Amal valve and a set up, also as you found out you can end up inadvertently turning the boost up higher than it should be which is dangerous, it's not that MFI is difficult it's just people try to think of it as EFI and apply electronic practices where as it's a mechanical affair.

It sounds as you are producing very little to no boost and that is why the car is sluggish which would show more on incline probably a result of the actuator being adjusted. Only other thing could be is a boost leak.

Martin