Art Library Trouble

Every time I upload an image to the Art Library, be in a map or some other tile, then drag it onto the board, it's always automatically shrunk down to 70 by 70 pixels (the side of one square on the grid) no matter how big the file size originally was nor what file type it originally was (png, jpg, etc.) is this supposed to happen by default? Is there a way or disable it? Am I doing something wrong?

It happens by default. If you're currently on the map layer, I think it'll be 140x140 though. If you know the size of the original, you can set it with right click -> advanced -> set dimensions, or else you can just drag the squares on the edges of the token to resize.

The problem I have is that simply dragging it to resize usually results in it coming out blurry or inaccurate. How come this doesn't happen in the tutorial video during the segment where the host uploads a map?

Hmm, that's not an issue I've had. I mean, sometimes it can be blurry for a few seconds, but then it finishes loading or whatever. As for being the wrong size, I think you can either match up the grid lines, or just input the dimensions (or a scaler of them).