These 2 theories about Umineko were actually posted on 2ch and on the official BBS.
Thanks to Dormeur for the explanations of the theories:
Enoura theory
>>My beloved hometown, the sweetfish river running through it.
The river is the Tokaido Line of Japanese National Railways (in 1986, called Japan Railways since 1987) which connects Odawara to Tokyo.
>>You who seek the Golden Land, follow its path downstream and seek the key.
Down line of the Tokaido Line is opposite to Tokyo.
So we follow the line towards Nagoya.
>>If you follow the river downstream, you will find a village.
On the map, there is a mark for a port, which resembles the character "里" (village). The port is Enoura fishing port(江之浦漁港).
http://maps.google.co.jp/maps?f=q&so...1&ie=UTF8&z=14
>>In the village, look for the shore the two will tell you of.
Regarding "漁港"(Gyokou), the word for fishing port.
"漁"can also be read as "ryou".
And "港" can be read as "kou".
The Kanji character "両"(means "both") is also pronounced "ryou".
And "口"(means "mouth", or possibly "tell" in this context) is pronounced "kou".
>>There sleeps the key to the Golden Land.
>>He who lays hand upon the key shall travel under the rules below.
>>At the first twilight, you shall lift up as sacrifice the six chosen by the key.
"Enoura" has 6 characters.
In Japanese, "e no ura"(絵の裏)means "behind a picture".
So there is a door or a path behind the picture of Beatrice.
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La Plata theory
>>My beloved hometown, the sweetfish river running through it.
The sweetfish represents Japan.
For Japan, "hometown" is Tokyo, the Japanese capital.
"River" means a line running through Tokyo around the Earth.
>>If you follow the river downstream, you will find a village.
"Village" means capitals of countries on the line.
On it, there are Buenos Aires, the capital of Argentina, and Montevideo, the capital of Uruguay.
They are opposite each other across the river, Rio de La Plata.
"Rio de la Plata" means "river of the silver" in English.
"silver" has 6 characters.
It's the key to the Golden Land.