ck.colors: no visible global function definition for ‘hsv’
f.pixconfig: no visible global function definition for ‘runif’
f.points.CKrige: no visible global function definition for
  ‘model.matrix’
f.points.CKrige: no visible global function definition for
  ‘model.response’
f.points.CKrige: no visible global function definition for
  ‘model.frame’
f.points.CKrige: no visible global function definition for ‘terms’
f.points.CKrige: no visible global function definition for
  ‘delete.response’
f.polygons.CKrige: no visible global function definition for
  ‘model.matrix’
f.polygons.CKrige: no visible global function definition for
  ‘model.response’
f.polygons.CKrige: no visible global function definition for
  ‘model.frame’
f.polygons.CKrige: no visible global function definition for ‘terms’
f.polygons.CKrige: no visible global function definition for
  ‘delete.response’
gpc.copyright: no visible global function definition for ‘RShowDoc’
plot.preCKrigePolygons: no visible global function definition for ‘par’
plot.preCKrigePolygons: no visible global function definition for
  ‘plot’
plot.preCKrigePolygons: no visible global function definition for
  ‘title’
plot.preCKrigePolygons : <anonymous>: no visible global function
  definition for ‘rect’
plot.preCKrigePolygons : <anonymous>: no visible global function
  definition for ‘polygon’
plot.preCKrigePolygons: no visible global function definition for
  ‘text’
plot.preCKrigePolygons: no visible global function definition for
  ‘points’
print.preCKrigePoints: no visible global function definition for ‘sd’
print.preCKrigePolygons: no visible global function definition for ‘sd’
summary.preCKrigePoints: no visible global function definition for ‘sd’
summary.preCKrigePoints: no visible global function definition for
  ‘str’
summary.preCKrigePolygons: no visible global function definition for
  ‘sd’
summary.preCKrigePolygons: no visible global function definition for
  ‘str’
show,preCKrigePoints: no visible global function definition for ‘sd’
show,preCKrigePolygons: no visible global function definition for ‘sd’
summary,preCKrigePoints: no visible global function definition for ‘sd’
summary,preCKrigePoints: no visible global function definition for
  ‘str’
summary,preCKrigePolygons: no visible global function definition for
  ‘sd’
summary,preCKrigePolygons: no visible global function definition for
  ‘str’
Undefined global functions or variables:
  RShowDoc delete.response hsv model.frame model.matrix model.response
  par plot points polygon rect runif sd str terms text title
Consider adding
  importFrom("grDevices", "hsv")
  importFrom("graphics", "par", "plot", "points", "polygon", "rect",
             "text", "title")
  importFrom("stats", "delete.response", "model.frame", "model.matrix",
             "model.response", "runif", "sd", "terms")
  importFrom("utils", "RShowDoc", "str")
to your NAMESPACE file.