From the picture you need to bring the lever more to the vertical position.
Yup, thats it.
If you look at the pic, you can see a "flat" on the locking lever. If you watch it as you move it, youll see it line up parallel with the face of the rear of the upper hand guard (yours is sloping rearward in the pic, and needs to roll forward). When it does, the hand guard should drop right in place. New or old, its usually a pretty close fit when in the right position.
As far as the lower handguard and the cleaning rod, if the new hand guard doesnt have the access point, youre going to have to duplicate it or leave the rod off. Even with the hole, sometimes, you just have to turn and/or wiggle the rod as it goes in. If the hole is there, give that a try first.