Cannot Select Tiles

load into the game begin listening to the narrorator
spawns in 5 workers explainging what they are used for
told to click and drag highlighted area
click and drag.....nothing happens
right click and drag......nothing happens
take control of a worker can then dig out said blocks
area stays highlighted
get told to dig out the gateway
click and drag.....nothing happens
manually dig it out get told to build a barracks
click the barracks button symbol appears with price next to cursor
click and drag.....nothing happens
unable to play game

note its all in the 3rd person view when i go to the first person and start swinging on the blocks i can destroy them and all my workers jump to action