I did it here with at least an inch on each side because this was not a counter depth or build-in type of fridge that needed only 1/2" of breathing room on each side. You need to *check * the *manual to see how much space is needed on each side and top for ventilation. Some fridges need Several Inches and if you enclose it too tightly you will void the warranty. This fridge did get a cabinet above: This fridge has about 3" on each side: also a cabinet above. The larger gap can be covered with trim as long as the breathing room needed exists. Its pulled closer to one side of the opening to allow for better door swing. This is the back of the fridge enclosure. It sits in a column like structure:

With chunks of drywall missing, you will need to use a setting type drywall joint compound to fill in the chunks. Setting type compound has a limited working time before it hardens, usually around 20 minutes, but read the package. Make sure you add just less than you need to fill in, not more. Most setting type compounds are difficult to sand. Once you are done with that, finish with a regular all purpose compound to get a flat surface. *edit* if the chunks are very small, you may even skip the setting compound step. All purpose compound shrinks and will cause you to apply more layers versus a setting compound which does not shrink.

The last set of images you posted look a nice professional taping job, but obvipously the quality of that job shows after the walls been painted. In the last set of images with painted surfaces that you posted, you can tell they did a bad sanding job. In some images, you see too much mud left on the taped joints makes them apear crowned and the center of the seam is left higher than the surface of the wall and that is quite obvious. After the came and touched everything up they should have smooth everything out and wet-sanded everything and you would have a beautiful flat surface. The third picture from the top (with little holes over surface) that called pitting, it's the air bubbles that were not properly filled or popped open after sanding. They usualy result from overmixing/undermixing the mud. Another reason why you get the bubbles is when not enough pressure is applied when going over the wet mud with a knife. In your case after the surface been painted to fix this all they had to do is apply a thin finish coat of mud over the area, sand it and prime it before repainting. Everything you show can easily be fixed, unfortunately people who they sand to correct this are incompetent and don't know what they doing and only create more work to fix this again. Demand from your GC to send people who know what they doing and don't let them out of the house untill they get it right. Maybe instead of taping crew, he should sand a painter, with quick drying compounds today, they can fix this and have it primed and painted in no time. Good luck.

Try to find some old house forums and/or local people who do plaster repair. Beware that people whose skill set is drywall are going to tell you that it all needs to come out. Very rarely does all plaster have to come out unless its been neglected or water damaged over a period of time. It may be you use a range of different techniques depending on what kind of damage. You may find that some walls have only minor cracks that can be simpy filled ,while some walls may have major bowing and large loose areas. arger damaged areas can either be re-done using old methods OR.... just attach drywall patches and fill in gaps with plaster (using bonding agent to get old plaster to adhere to new plaster). Whatever you do, please dont do the thing of putting drywall OVER the old plaster and butting it up against the baseboard and window and door trim. Thats just plain ugly Ceilings might be the one surface you decide to have drywalled - looks like we are seeing ceilings in your pics? Gravity has greater effect on ceilings, so damage can be a lot worse than walls. And, since theres no trim to contend with up there, its a lot easier. If you want to start a thread and post some pics over on the old house forum, I think youd find a lot of us could advise in more detail.