I don't know about the yellow markings on the leaves (I can't really see them from the photos, but that might just be me).
I do know that sometimes when a phalaenopsis is growing in a low-humidity environment, sometimes the edges of the leaves will turn a slightly different color and/or get dry or brittle.
I am not sure if I am understanding your problem with the leaves "growing down"... It is my understanding (an personal experience) that phalaenopsis leaves will start to "grow down", meaning that the tips of the leaves will start to curve towards the floor. In all of my plants, this has happened in my mature phals once the leaves have reached a certain size - they would grow "straight" but then they would start to curve down without any changes in growing condition. If this sounds like what is going on with your phals, then I would say don't worry about it and let them "do their thing".
If this is not what you meant, maybe if you could phrase it a different way, we might be able to help more. Let us know!