Zoltor, please avoid double posting, as it is against the forum rules. You can review our forum rules here. Thank you.
Zoltor's first solution wouldn't work, because no matter where in the tileset the tile is, all A-tiles are under the player and can't be set to above the player.
And his understanding of the Star-Setting in passability is also wrong: a Star in passability means that the tile is displayed above the player, nothing else.
So if you're using a tile there, then you need to set that tile to Star passability.
However:
If you're using a picture to display the arc (which is unneccessarily complicated in my opinion, better set the tiles for the arc to Star), then you need to set the picture to a higher Z-Level to display it above the player.
I'm not sure how that is done as I haven't used that yet, but if I remember correctly the Z-Level of a picture is dependend on it's number - try using a higher number in the picture command, something above 1000 or so (IIRC the player is somewhere around several hundred in the Z-Level)