Raising Drawbridge / Can't Climb Tower Stairs

I've searched and searched for someone else who's posted this same problem, but haven't found it anywhere, thus I'm assuming it's not a common problem. I cannot climb the tower stairs. I can get up the first couple of steps, but can't access any higher. I had some similar trouble with the circular stairway down at the Crypt at the beginning of the game. I was able to maneuver around this by adjusting the pgup / pgdn keys. I've tried the same method with this stairway, but nothing seems to work. Can anyone help me? I changed from high res to low res (and restarted the game) but continued with the same effect (or diseffect LOL). Thanks for any input.

As you have discovered, this game often requires PageUp/PageDn adjustments to get where you're going. I did not have any trouble with circular staircases. I hold the forward key (num depressed and at the same time press either numpad 4 or numpad 8 depending on the direction.

Good luck getting unstuck.

Correction - numpad eight for forward and numpad four or six for circling the stairwell.