How can I get to Chung King Mansion from Macau?

Well, you can take ferry at Macau Outer Harbour Ferry Terminal, and get off at HK- Macau Ferry Terminal. The schedules are from 07:00 to 23:59 with the interval of around 15 mins. It takes around 55 mins on the way.
After arriving, take Island Line at Sheung Wan Station, and get off at Central Station. Then transfer to Tsuen Wan Line to Tsim Sha Tsui Station, Exit E. It takes around 20 mins. After, walk to the mansion.

From Chung King Mansion to Disneyland, take West Rail Line at East Tsim Sha Tsui Station, and get to Nam Cheong Station. Then take Tung Chung Line to Sunny Bay Station and transfer to Disneyland Resort Line to Disneyland Resort Station, Exit A. After that, walk to the theme park. :-)