Thermopane glass that has the low-e coating is not ideal for plants. Most does have it. I go for single-glaze glass. A cold frame can be super-simple or as complicated as you want. The simplest is make a box out of whatever you have, 1x or 2x boards wide as possible. Make the outside demension of the box the same as one or more sash. Make up a growing bed and place the box on it sloping somewhat toward south, 10 degrees or so, just push the south end down and prop up the north end and heap up soil and pile mulch on the north side for insulation. If you don't have hinges just set the sash on the box. On sunny days around mid-morning take the sash off, put them back on mid-afternoon. Cloudy days leave them on or put a block under the sash to ventilate it a little. Works just fine. Take you about 30 minutes.

lsst is exactly right. This is how I've aged some very intricate designs on frames, embossed pieces on furniture, etc. May I add though....use a dead-flat sealer on your item first. A dead-flad sealer brushes on easily, is water-based, and it will protect the original surface. Once you apply the dark glaze, using the sealer first, you won't have too much dark glaze sticking where you don't want it. The dark glaze, using the sealer first, comes off so much easier with that slightly damp cloth. This comes from experience. Not using a sealer first, but using a dark glaze over heavily embellished gold frame. The frame was old and porous and sucked up way too much of the dark glaze. Using a sealer on the second frame, I had lots of control over the glaze...how much I wanted to keep, how much to remove. The Dead-Flat sealer will not change the finish. Whereas a sealer with any gloss, will.

If you use the correct procedure and work carefully it is very easy to do. First off, give yourself plenty of room to work. Begin by marking where you want the stub out to be, then make a horizontal line on the wall about 4" above and a second horizontal line about 4" below. Begin on either line at a point about directly above the point where you wan the stub out to be and punch the saw into the wall, then cut horizontally until you feel a stud. Next gpo back to your starting point and continue cutting the horizontal line in the opposite direction until you feel the stud on the opposite side. Now go to the other line and repeat the process. You can then cut down on each end, keeping the saw tight against the stud and remove the sheet rock. Keep the sheet rock intact because it will fit back in the hole perfectly to close up when your done. Cut two pieces of 2x4 about 3" longer than the distance from the bottom to the top of your hole. On either side of the hole slip a piece of the 2x4 in so that the 2x4 is sistered tight against the existing stud and the tips of your 2x4 are slightly behind the sheet on both the top and bottom. Secure the short 2x4 to the stud with a couple screws. Now measure the horizontal distance between your new 2x4's and cut a piece of 2x4 to make your blocking. Insert the blocking and secure each end with a couple screws, then you can attach your drop ear to the blocking. Once you have the drop ear mounted mark the location of the drop ear on the sheet rock panel you cut out, drill a hole for the stub out, then set the sheet rock back in the hole and secure it to the 2x4's on each end with a couple sheet rock screws. At this point you will have a slight gap equal to width of the stab saw blade to mud and tape.

I would love to know what you ended up deciding as this is EXACTLY the issue I am having right now. It would be foolish to raise all the windows; the top of the door and window casings all absolutely need to align with specially if they are right next to each other as yours are. So the door casing needs to be raised. So you can either have an extra wood piece fitted under the casing and above the door, or pay for the taller door. Don’t just leave it the way it is now or it will infuriate you every single day 😢😢.