Bornholmsgatan 8C, 271 39 Ystad, SwedennRegister here. For those visiting for the first time. Go to the ferry to Poland, then turn right before the gates to the parking lot. Then walk to the above address, pass the fence on the left and the buildings. Turn left, and there you'll find the building. Generally, it's poorly marked. I wouldn't have found it if I hadn't asked someone.
I was very pleased with the entire boarding process. It's a small terminal, but we had everything we needed. There was a waiting room with seats. Seating may be limited due to the large number of foot passengers. The ticket desk and information/customer service desk were very helpful. There were many open stations. There was a vending machine on site, so you could buy something to drink. A bus arrived at the exit and took us directly to the ferry's car deck. Everything went smoothly and in a very pleasant atmosphere.