Properties DoubleBuffered and ParentDoubleBuffered was added recently, they are not yet in Lazarus 2.0.Lazarus gives some dialog with "Ignore and continue loading" (for projects).You can use Lazarus trunk or fix package manually.
from this address "https://github.com/jbsolucoes/ucp/" but with the version of lazarus 2.0.0 without problems worked. When updating the lazarus to 2.0.2 the problem appeared. Thank you for your contribution