I'd try a couple of things to make the daggerboard? (retractable centerboard actually)
more easy to deploy and retract.
First, as suggested, take the screws out of the deck plate and examine the pivot points,
the bushings/bearing areas where the pivot points seat, and the "stopper" that prevents the CB from retracting too far.
The fact that the handle hits the deck when the CB is fully retracted is a good clue that the "stopper" is not adjusted or installed correctly.
I have a Rio M with pretty much the same CB cassette (I think) and I needed to take the deck plate off and make sure that the CB had enough clearance to move up and down in the cassette freely.
Perhaps a few strokes with a file on the "tight spots" would free it up.
Also, for a "lubricant" (that does not attract and hold sand and other foreign particles)
use a bar of soap.
When you have the cassette opened up, rub a bar of bath tub soap over everything!
Then before you go out each tme, rub the areas of the CB that contact the lips of the gaskets with the bar of soap. Also "lube" the lips of the CB gasket in the bottom of the board with the bar of soap.
Also, with the stiff gaskets that they've decided to use on these boards, it's necessary to make sure the CB comes all the way up through the gasket for it's entire length.
If the CB sticks through the gasket at all, it's nearly impossible to move it either up or down.
Stepping down on the back of the handle, with the CB nearly all the way up, so it comes
completely inside the cassette and isn't "trapped" by extending partially through the gasket is a pretty necessary thing to do.
Also, if this CB cassette has the plastic "guides" on the sides, and the plastic "lock mechanism" (either all the way up or all the way down in 2 "detents") make sure the plastic parts are fully seated in the sides of the cassette and they are "retained" from
moving inward and interfering with the free operation of the CB.
Hope this helps,