The gotchas here seem to be a mix of Ireland and '62 - hex trains,
overlapping routes, mergers without a Director's consent.

The number of ORs per stock round increases from 1 to 3 with phase,
like 1825.

In a stock turn you either sell shares, buy one share, or auction a
company. 5 companies are available to auction in phase 1, 4 more in
phase 3, and 3 in phase 6.

If you auction a company, the winning bid is paid to the bank, not the
company. The winner of the auction sets a par price and buys 20-50% of
the company at that price. You can't place a bid that would leave you
without 100kr (2x minimum par price of 50kr) or if you are at cert
limit, so you always can and must start the company you won the
auction on. You can't auction a company that has been started and then
acquired (removing it from the game).

Buying and selling shares is pretty normal except you can't sell a
share you bought in this SR, 1862-style. (So eg if I go into the SR
with 20%, buy 30%, I have 50%, I can sell down to 30% but not below
that). Stocks move half as many steps left as the number of shares
sold, moving down. You can't cause a company to have no Director by
selling. You can't buy more than 60% of a company.

Companies that are sold out at the end of the stock round move one
right. Companies that are 50% sold float - also at the end of the
stock round, which I think means there's an edge case where a player
was holding shares at the start of the SR, 50% of it was sold during
the SR, but someone then sells down again and it doesn't float. Full
capitalisation, further income only on withholding.

You get one lay or upgrade; you can upgrade if you can reach new track
or increase the value of a route.

Trains are hex trains - an (eg) 4H runs 4 hexes _plus_ the one it
started in, like 1862 freight trains. Also like 1862, trains can run
on overlapping routes, but you only score each revenue location you visit
once. Autorouting may struggle with >1 train - but it's a small map so
I think we'll cope.

Move left on withhold (but companies can't fall to 0 and vanish); on
pay out, move right 0-3 times if payout < stock price, < 2x stock
price, < 3x stock price, >= 3x stock price.

You can only buy a train from another one of your own companies. You
must pay at least a fifth of the face value, and the price must be a
multiple of 5kr.

There's emergency money raising - but if you don't have enough cash,
you put all your cash into the company and don't go bankrupt (nor does
the company), and next OR the Director tries again. (One hopes they
have some other income).

Last - but not least - companies can merge. This is described as
"acquire", but it is more like a '62/Ireland merger than an exercise
where company A buys out company B.

Company A can acquire company B if:
The Director holds more shares in the two companies than all other
players do together.
A has a route to one of B's stations.
A and B combined do not have more than six tokens on the map.
Both companies have performed "purchase trains" at least once.
Either both companies or neither have performed "pay/withhold" this OR.

Like '62 you can merge/acquire at the start or end of your OR. You
carry out these steps:

1) The stock price of A is set to that of the lower priced company
plus half that of the higher-priced company, rounded down.

2) Each player exchanges their combined shares for half as many shares in
A. Odd shares are exchanged for shares in B. If the Director of A now
has only one share in A, they remain the Director (but see 4 below).

3) Clockwise starting with the Director of A, each player with a share in
B must pay half the stock price of A to replace it with a share of A,
or if that is not possible they receive half the stock price of A.

4) If the Director of A now has two shares, they take the Director's
certificate.

5/6/7) A takes all B's trains, money, and tokens (but if two tokens in one
hex, B's token is removed.) B and its shares are removed.

8) If no-one now has the Director's certificate of A, it too is
removed from the game - but I think if this is the case, the Director
of A has made a horrible mistake.

9) If the Director of A did not get cash in 3) for being unable to
replace a share of B, they may buy any number of shares in A for half
the stock price. (Why does this not depend critically on starting with
an odd or even number of shares in B? I don't know.)

There's a '62-style endgame procedure after the OR in which the first
10H is bought. First, each company performs "purchase trains".
Companies with no trains after that are removed. Then there is a stock
round with no auctions, and where share sales don't reduce the
price. Then perform three ORs where companies can only run trains and
pay out.

The game also ends immediately (even during the endgame procedure?)
after an OR in which a company hits 400kr.