No pics right now, but I'll try and describe this as clearly as I can manage.
Assuming you're talking about building a door/frame like a traditional house has (though usually a little shorter unless you're building your yurt with "tall walls").
The door frame itself is what it is - a pretty standard 2x6 job except for the threshold which should extend out and follow the contour of the yurt's drip edge, overlapping by an inch or two so water doesn't collect between the threshold and yurt floor underneath. You'll also want to seal this union with some type of waterproofing silicone RTV or the like. Roof leaks aside, door sills are probably the most vulnerable place which could allow water to enter the yurt. Additionally, you will need to build some kind of 2x4 or 6 "wings" on either side of the door frame for your clamp boards. (more about that in a minute.) Toenail (actually screw as you might want to take this apart someday) the door frame down to the floor decking on the outside bottom corners of the frame so the screws are hidden from view when everything is assembled.
The ends of the lattice are typically bolted to L brackets affixed to the outsides of the door frame behind the "wings". Where the rivets or bolts go that hold the "X" parts of the lattice together, you would just use a bolt and wingnut through the hole instead. Depending on your yurt size and design, you should have 3-4 of these on each side.
On the outside of the yurt where the yurt covering meets the door frame, there will be maybe 6-8 inches of "extra" fabric. The outside facing part of the wings you built will have a 1/2 x 1/2" or so channel routed in them running the entire length of the face vertically. Wrap that extra yurt fabric around a 3/8" dowel of the same length and set it into the channel. You will have another 2x4 or 2x6 (finished with spar varnish or the like) "clamped" down against the dowel and canvas, secured with carriage bolts going thru to the inside and nuts on the back.
Roof fabric should run just over the front facing of the door header, diverting water and snow. Several different ways to secure this piece, just use your imagination here.
Does that all make sense?
