Bingo. He's expecting gold to appreciate more against EUR than the USD in all likelihood. I would suspect he anticipate that the EU will eventually have to join into the currency depreciation game. I believe he's right.
"long gold in euros" i guess that expression means he expects gold to up and the euro to go down in value. correct?
He would have been better off buying gold in yen though. It's near record highs. You can see the charts for different currencies here: http://www.bullionvault.com/guide/gold/Gold-chart
No, he is short euros and long gold. Think about it this way. He borrows some euros, exchanges them for dollars and then goes off and buys some gold with the dollars. So he owes the bank euros (i.e. short euro) and he has some gold coins in his pocket (i.e. long gold).
if he sells the euro/$us cross he is expecting the euro to go down against the $us? what am I missing?
He's betting Gold will go up more versus EUR than it will go up versus USD. He may think gold is going up, and both USD and EUR are going down relative to gold, but EUR will be weaker than USD.
It's impossible to know for sure. I would take it to mean he literally bought gold, denominated in euros at a brokerage where he held euros.