Hrqls: Yes A2345 is a straight.

You always use the best five card hand from each player to determine the winner. Whatever cards are left over do not matter at all. So in your example both players have the same straight and the pot will be split between them.

Minimum amount to play in BK poker is the size of big blind. (Unless it has been fixed recently. You really should be able to play until you lose all your money.)

And about the side pots: you cannot win anymore from any player than you put in the pot yourself. For example P1 calls 10, P2 raises all-in 50, p3 raises to 100, p4 calls and then P1 folds. Main pot will be 10+50+50+50=160. Whoever has the best hand in the end will win this. P3&P4 will also be playing for a side pot of 50+50=100.