I have read this to learn about ように: http://www.guidetojapanese.org/learn/grammar/surunaru
Part - 1 Going by the definition of よう which is more like "appearance/manner", I don't quite get how the constructions are made in which ように has more of an interpretation of "so that". I have read its similar counterpart, ために and the difference between them (Difference between ために and ように), but I still can't arrive how from the literal meaning of appearance or like, we can reach a meaning like "so that"
Ex 1: 速く泳げるように、毎日練習しています。
Part - 2 As per my understanding, we need to use ように to allow us to modify a verb with another verb. But when we use the negative form of the verb in plain form (ない form), it is more like an adjective. So why do we use "ーないように some other verb".
Ex 1: 忘れないようにつけてあるんです（丸をつける）- I have marked the circles so that I don't forget.
Ex 2: 工場ができてから、この近くの海では泳げなくなりました。 Since the completion of the factory, I was not able to swim in the nearby sea.
As example 2 shows ーなくなります is also used. What difference to the meaning will ーないようになる add?
Thanks for any help.