HighlightTangle: no visible global function definition for 'Rtangle'
HighlightWeaveLatex: no visible binding for global variable
  'RweaveLatexSetup'
HighlightWeaveLatex: no visible binding for global variable
  'RweaveEvalWithOpt'
HighlightWeaveLatex: no visible binding for global variable
  'RweaveLatexFinish'
HighlightWeaveLatexCheckOps: no visible global function definition for
  'RweaveLatexOptions'
Htangle: no visible global function definition for 'Sweave'
Hweave: no visible global function definition for 'Sweave'
col2latexrgb: no visible global function definition for 'col2rgb'
css.parse.color: no visible global function definition for 'colors'
css.parse.color: no visible global function definition for 'col2rgb'
external_highlight: no visible global function definition for 'tail'
latex_color: no visible global function definition for 'col2rgb'
makeHighlightWeaveLatexCodeRunner: no visible binding for global
  variable 'RweaveEvalWithOpt'
makeHighlightWeaveLatexCodeRunner : HighlightWeaveLatexRuncode: no
  visible global function definition for 'RweaveChunkPrefix'
makeHighlightWeaveLatexCodeRunner : HighlightWeaveLatexRuncode: no
  visible global function definition for 'SweaveHooks'
makeHighlightWeaveLatexCodeRunner : HighlightWeaveLatexRuncode: no
  visible global function definition for 'RweaveTryStop'
makeHighlightWeaveLatex_WriteDoc : HighlightWeaveLatexWritedoc: no
  visible global function definition for 'RweaveChunkPrefix'
simple_detective: no visible global function definition for
  'getParseData'
subsetParseData: no visible global function definition for
  'getParseData'
Undefined global functions or variables:
  Rtangle RweaveChunkPrefix RweaveEvalWithOpt RweaveLatexFinish
  RweaveLatexOptions RweaveLatexSetup RweaveTryStop Sweave SweaveHooks
  col2rgb colors getParseData tail
Consider adding
  importFrom("grDevices", "col2rgb", "colors")
  importFrom("utils", "Rtangle", "RweaveChunkPrefix",
             "RweaveEvalWithOpt", "RweaveLatexFinish",
             "RweaveLatexOptions", "RweaveLatexSetup", "RweaveTryStop",
             "Sweave", "SweaveHooks", "getParseData", "tail")
to your NAMESPACE file.