Newbie rigging questions

[WhiteRabbit]

In the manual it shows a section of rope/line that takes the shock of the forestay. My boat appears to have had one originally but is now missing it.
What is this bit called? I’ve seen it called a shock cord in the literature but the google results from that term aren’t super helpful.
Can I make my own?
What kind of line should I use? (Stretchy vs non)
Is it bad to run without it?
https://imgur.com/a/7OYvOUK/

I got the boat for cheap because it didn’t have any sails. I have since purchased a jib and main sail from Intensity Sails. I put the sails on to test fit them and I found the boom on my boat doesn’t go low enough on the mast to get the sail tight because there’s something intentionally installed in the track preventing it from going lower. It also looks like the boom downhaul cleat is screwed into this track limiter. I’m tempted to pull the bit out and cut it down but I figured I’d ask you guys first.
Is this adjustable?
I can’t find any clear photos of what it’s supposed to look like online so could someone weigh in and tell me where my setup is wrong?
https://imgur.com/a/Vn3U36z/

The end of the boom is probably the most confusing part for me. I’ve figured out that the pulleys on the boom are for sail reefing but I can’t figure out how the main sail clew attaches to the end of the boom. The end of the boom has two holes to attach to but I’m just not sure how. Some of the illustrations make it unclear if the clew gets its own bit of line to attach to or if it’s somehow attached to the reefing line on the boom.
Which is the way it should be?https://imgur.com/a/RzlJjY4/

I see so many variations to how these are set up but I’m really just looking to put it as it was originally designed. I’m new to sailing and I’m keeping the rigging stock for now. I apologize if I’m calling anything by the wrong name, the jargon is new to me. Thanks so much for your help!

[GreenLake]

From your pictures, the height of the boom looks about right (assuming that your mast is full length and hasn't lost any over the years by action from some prior owner).

The boom normally is 24" above the deck and the top of the mast track is 20' 6" above that location. If there's less room than 20'6" your sail may be too long for your mast, and you may have to have it adjusted. You don't want to arbitrarily lower the boom, because you may want to rig a boom vang later (it helps control the boat in windy conditions, among other things). If your boom is 20' 6" below the mast track end, or even a bit more, and your sail isn't stretched at all, then they sent you one that is too long for a DaySailer, and you should get it fixed under warranty.

The photo does not show the effect of too little luff tension, but it seems that you haven't tried to stretch the foot of the sail (between mast end end of the boom). You'll want to rig an outhaul.

[GreenLake]

You are correct that what you have installed is a reef line. You can see my reefline in the photo, it's black/white and may look gray. As you can see it's much thinner than what you have (in general, any line that you don't need to hold on to, can be made much thinner than factory original, if you go to modern, low-stretch rope. (See "Rope for various lines")

To attach the end of the mainsail, you use an outhaul (red and white in the photo), a line that pulls the clew closer to the eye at the end of the boom.

You can see one on this picture.



what you can't see is that the outhaul line goes forward on the hidden side of the boom and to a cleat that is closer to the middle of the boom.

(Ignore the end-boom mainsheet, as I assume you have center-boom sheeting).

I'm using one double block (we don't call these "pulleys" when they are used on a boat) and I also run the outhaul one more time through the clew cringle. In combination that makes for a 3:1 purchase which you will need if you want to tighten your outhaul in any conditions where there's a bit of wind in the sail.

[GreenLake]

I'm not familiar with anything "taking the shock of the forestay". If you found this in a manual, you may need to help us out by taking a picture of the written explanation.

The forestay is usually wire. Sometimes people attach a line to the end to pull one while the mast is being raised. That's detached when the mast is in place and is any standard rope.

[GreenLake]

The rigging and sails for the DaySailer III should be compatible with the other versions of the DS. As far as I understand the main difference is some detail of the hull shape (higher freeboard). That difference was deemed sufficient to affect competitive racing and therefore a DS III is not "class legal". However, all the basic rigging issues should be the same, so I'm going to move your post to the "Rigging" area.

[GreenLake]

Just in case any other newbies stumble on this discussion: there's an introduction to some basic topics of sailing a DS.