How long has the tile been up? Its possible that some areas of thinset haven't fully cured yet. Glass doesn't breath so thinset takes longer to set up. IIRC recomendations are to give it a few days, up to a week to fully cure (setup). Ditto with the mortar or concrete behind the tile, how long has it been drying for? The tell is the dark areas where the sheets meet. That just looks like different areas of thinset drying at different rates.
The first pic looks like there's moisture behind the tile. Tile isn't fully set in the thinset so moisture is in the gap behind the tile or, again, the thinset hasn't fully cured. To have moisture in a void behind the tile means they didn't install it (glass tile) right. Your supposed to spread thinset with a notched trowel, then spread it flat, then embed the tiles. It is a known problem when the glass tile is only embedded in knothed thinset and the pattern show right through the tile.
If you reply and say its only been up a couple days I say wait. If its been a solid week then thats a different issue.