Satellite dishes are not allowed in Aran Court and AFAIK legal action is being taken against those with dishes already up. It was part of the planning permission for the development that no dishes would be erected.
As the Management Company owns the external walls of the buildings you are not entitled to drill into them or attach anything to them. Doing so could be considered criminal damage. Balconies are also the property of the management company though the resident has exclusive use of these but again, dishes etc should not be erected on them.
UPC cable and broadband is decent in the area, you do miss out on some channels but if Sky is that big an issue perhaps you should have looked into that before you moved.