kuwakojoku

Super interesting 棚 that is also used in 表千家. It's a 仙叟好み, and can work a bit like a 長板. It's had a lot of changes over the times: 又玄斎, for example, changed the way the 柄杓 is facing to it's current, 裏千家 form; and since 淡々斎 the books have slightly diverging ideas about which 建水 is appropriate to use and how to deal with the 蓋置.
Inspired by an arrow stand, so quite a good one to use for May
表千家 also uses it, but places the 柄杓 facing towards the host.

To place the 柄杓: ready, then R grasps the node from behind, turns it away from you, L supports at the bottom (just release briefly to get around the pillar)
濃茶 with 平建水: 蓋置 goes in front of the 建水, not behind, after the guest has asked for 拝見. Pick up 柄杓, かまえて, then move 蓋置 back with R; then put the 柄杓 on it with L.
薄茶: Place 茶碗 to the wall, then take 建水 with both hands

建水:
- Newer books say it has to be used with a 平建水; older books say that you can also use other 建水. I think for 5.5, for example, a 槍の鞘 one might be nice!
- Traditionally, a 楽建水 is used, but 唐金 is also fine.
水指: Traditionally, it's used with a Dutch high one.
The 蓋置 officially lives on the middle shelf. So if you're not using a 平建水, that's that. However, if you want to come back with the 建水, you put the 蓋置 on the lower shelf (sort of as a sign for the guests that the show isn't over yet). However, it stays there and becomes quite awkward to remove when you put the 建水 in front of it.
- It's quite nice to use it with a crab, even though then placing the 柄杓 as described above is difficult.
- A shell would also be nice.

Since the 柄杓 normally will already be there, you need to put it on the 蓋置 (presumably). KM26 said she had a notion that it might stay on the 棚 until it's needed, which would be very 長板-esque.
Normally, you'd sort out the 拝見道具, then 水次, leaving the 蓋置 on the bottom shelf, and coming back with the 建水 after 拝見.
Older books put the 蓋置 temporarily on the lower shelf to the left, only to then return it to the middle shelf after leaving with the 水次. This is very tidy, but maybe a bit boring.
総荘: Here, KM26 had a nice suggestion. Come in with the 建水 before the 水次, so you don't have the awkward motion. Then, after the 水次, leave the 帛紗 on the lacquered 水指 lid and go.