Was it 5mbtc as the minimum withdraw? As long as I remember I have ever made a withdrawal less than 5mbtc, unless they have increased it recently. It is always bettee to ask with live support if you want faster answer of any questions you have.
I made small withdrawal in couple weeks ago. I am able to withdraw 4 mBTC, 3 mBTC and even 1 mBTC. Maybe 5 mBTC minimum withdrawal applied when the minimum stake was at 5 mBTC and it was a long time ago.
Same here, Withdrew like 4mBTC, though quite long ago. I heard earlier one had to withdraw atleast 5 mBTC, but recently one mate made a withdrawal of lower stake.