New with RPG Maker, and would like some help/tips Options

[iSuck]

A friend and I are making a fan game, and we need a bit of help since we're completely lost.
Anybody willing help us a little bit on a few problems?

How do you turn off music after you turn it on? I know this isn't very descriptive so I'll give an example.
Our character has a little radio in his room, I made the event so he can turn it on, but the music forever loops.
What do you do to make it turn off when interacted with again?

Another problem, when our character walks, there's an annoying pink flash. Is it the sprite's fault?
I was worried about the transparency, but when he stops walking, the flashing stops. So I'm not too sure.
We used a dark green for the transparent color, and pink is the opposite of that, so that's why I'm wondering.

Also, how do you change the overall speed of the character's walking?

[iSuck]

Extremely late reply, I'm so sorry!

Thank you so much! I'll try this out!

We did the click-the-background thing but it still wouldn't work for us the last time. Probably the character sheet though!

And for the character sheet, we made it that way on purpose. You didn't have to edit it.
But thank you tons!