Laser XD Sailing have recently published some short instructional videos on YouTube and on their web site. They are well produced with real time and slow motion video. There is another good one on roll gybes, but unfortunately they have blocked the embedding function so you will have to find it via their YouTube account. Here is one that they have let me publish on roll tacks in light air.
Their web site looks like it is still under construction, but they have some some good beginner/intermediate information.
This is a sample from their rigging guide.
In medium air, the goal is maximum power. The vang should be tensioned just enough so that it isn't sagging while block to block. Having the mainsheet block to block will create maximum leech tension and power in the sail. As the boat becomes overpowered, begin to tension the vang to reduce power in the sail.
The draft of the sail should be set just under a full sail, about a hands length at the boom cleat or 15 cm (~6 in). The cunningham should be on just enough to take out the large diagonal creases. As the wind increases, depower the rig with cunningham and vang. The cunningham will pull the draft of the sail forward and reduce the draft slightly. It is important to set the outhaul and cunningham so that the draft isn't less than 10 cm (~4 in).
The traveler must be tight in order to avoid the boom from moving towards the center of the boat. If the boom is still moving towards the center of the boat, tension the vang just enough to help the boom to stay in the correct position.
Laser XD Sailing