Slope, tile collision, obj collision (help needed)

How do I make tile collision and slopes work if the player is 32x32 while the tiles are 16x16? furthermore how can I design it to be functional with obj wall collision?
I wanted to have slopes and stairs for my 2d platformer.
I've been following Shaun Spalding's tutorial on tile collision and slopes, but I need the player to be bigger than the tile size. I really need help!
Tile Collision:


You could post in other forums?

You need to check additional points. Instead of checking the four corners alone, you also need to check the middle. Technically, any 2 points you check need to be at MOST the size of your tile apart.