I think @Daffy got confused. Private key importing is still on the dev cloud and hasn’t been pushed yet.
You can simply add your Coinprism address on the settings screen on GHcloud.
It will show your stats on the GHcoin page. You can then either create a new BTC address on GHcloud and make that an asset address and transfer your GHX over. If you do that you’ll have to add the BTC address associated to your current asset address on the ROI tracker to include it in your stats.
Not sure when we will be pushing the key import since there is quite a few other fixes and updates that go into the next cloud update.