Withdrawing HTML5 offline wallet

Hiya all

I'm hoping some of you might be able to clarify something for me and put my mind at ease. Probably a full on newbie question but I havent been able to find answers by searching online.

I've had some bitcoins for some time and been pretty happy with how things are going. Anyway, lately I thought I should try something new and I went for HTML5. Ended up going with Bleutrade, having had issues with tradesatoshi, and noting Bleutrade seemed to have the least bad reviews.

So, I sent over some bitcoin and traded it for HTML5, all of which went very well. However, now it does not let me withdraw the coins into the wallet I downloaded off the HTML website (figuring I'd prefer keeping things offline). The only currency that I can seemingly withdraw is BTC, which of course would result in a loss right now.

Is this normal for HTML5? Are my coins safe with Bleutrade? I'm just worried, given I was always able to cold store my other coins. Now I'm put off doing any more trading on the site, although I would have liked some more HTML5 coins.

Maybe this is all super obvious to the experienced trader, but it's doing my head in right now.

Any helpful advice would be really appreciated.