So XT means Cross Trade(buyer and seller are using the same...

So XT means Cross Trade
(buyer and seller are using the same broker).

CXXT means Center Point Cross Trade
(buyer and seller are using the same broker and the trade goes through at the centre point between the buy and sell price) - in this case 0.0025

Retail apps, like commsec only show the price to three decimal places, so 0.002 or 0.003 but change the colour to red/green.

The reason this happens (I think) is for psychological games to play, make the colour look red and make people nervous, then sell...
Or it could be to trigger "stop loss" thresholds (unlikely here).... where people set up automatic buys or sells if the price reaches a limit.... kind of like a set and forget, so you don't loose too much if the price falls. Unlikely because there hasn't been lots of price movement for people to set these conditions up.

It's a bit of games being played in my opinion.

I hope this helps