was the ram hard to reinstall?
if the packing on the ram was tight it may be causing a drag.
the freelift cylinder has to move freely till it gets to the end of its stroke, then the secondary lift cylinders pick up and start extending the outer channels after the carriage gets to the top.
As far as this 'load lowering valve' your speaking of there is not a 'lowering valve' in the cylinder, the only valve that would be in the cylinder is the 'safety valve'. This valve is there to keep the cylinder from dropping too quickly if a hose ruptured. Now if by chance you installed it backwards it may cause this problem. I have seen those cause several problems related to lifting and lowering both.
So you may want to pull the ram back out and make sure it is still intact and try turning it around.