Solved. Thank you, Cold.

ha, when I returned to the quest giver that said 5000

I too struggled , using the latest chrome & win 7, went round a few casinos, eventually found a slot that worked. Also I don't think the new variable limit is working quite right, I'm lv11 and the quest box says 2000 chips to complete, however it took 5000 to finish it :)

I have no clue what is going on.

When I click on a slot machine, nothing happens. I dont move to the machine and when the machine is occupied, I don't get the message.

I tried every machine on all 4 floors of James's casino and the other two casinos on the square. When Coldblooded mentioned he could play, I tried again ... nothing happened. But when I went to nicolasb's casino, I was allowed to play at a slot machine. I then left and tried the casinos at the square again and couldn't play again.

I cleared the cache again and logged in again. Tried the machines at James's casino again and couldn't play. But I could play at James's other casino after several tries and managed to finish the mission.

Using the latest version of SRWare Iron (updated 2 days ago) and have no clue what could be wrong.