Cp88
The slide does come off, complete with the barrel. All you need to do is remove the Allen screw at the front of the slide. This is just below the muzzle. If you then hold the slide and turn the release lever until it is vertical, the slide/barrel can be slid forward along its rail. Be aware that there is some slight spring pressure which will push the slide forwards. You can then access the internals of the lever, and also the slide locking system. My own CP88s don't have a problem with stiffness of the lever, so it looks as though yours needs some lube, or a trip to the seller. The only problem with opening it up is it may invalid any warranty.
To reassemble, fit the spring over the guide rod piece, locate the slide on its rails, set the release lever to vertical, and push the slide into place. The slide can then be locked by moving the lever anticlockwise. Replace the Allen screw and the job's a goodun. If the spring guide falls out during disassembly, it drops back into the frame with the groove at the top and as far to the rear as it will go. The front of the spring locates in a channel at the bottom of the slide, directly behind the fixing screw hole.
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