Moving through a solid object through another

I was wondering if it were possible to have an object, that usually cannot move through a Solid object, go through a non-solid object that is overlapping a solid object. Because I'm crap at explaining things, I created a simple pic to show what I mean:

<img src="http://i51.tinypic.com/sfkri9.png">

So basically, the player cannot pass through Object One, as it's solid, but he can Object Two, which isn't solid. What I was wondering if it were possible is for the player to be able to move through Object Two even while it's overlapping Object One.

Only if you make you own movement for the player.

Then I guess it wouldn't work with my example here:

I want the player to be able to dig into the terrain. This works when I use the canvas object, but seeing the canvas object seems to be only as big as the screen size, I needed a different option to "mining" that doesn't use the canvas. Or is there a way to increase the canvas object size?

can you post a cap ?

On the link I had on my post before this one (from the Examples and Tutorials section of the forum) there is a download to my original cap, which pastes the level onto a canvas object. The newer version I have been working on is here:

http://dl.dropbox.com/u/31490769/terraingen2.cap

Its a bit newer, but doesn't use the canvas object and keeps the terrain blocks as separate objects.