Installation fails

[sjPlot]

Installing the package fails and exits with an error:

devtools::install_github('ggthemr', 'cttobin')
Installing github repo ggthemr/master from cttobin
Downloading master.zip from https://github.com/cttobin/ggthemr/archive/master.zip
Installing package from C:\Users\Luedeke\AppData\Local\Temp\Rtmpygkd1x/master.zip
Installing ggthemr
"C:/PROGRA2/R/R-311.1/bin/i386/R" --vanilla CMD INSTALL
"C:\Users\Luedeke\AppData\Local\Temp\Rtmpygkd1x\devtools7cc4f426412\ggthemr-master"
--library="C:/Users/Luedeke/Documents/R/win-library/3.1" --install-tests

• installing source package 'ggthemr' ...
  ** R
  Error in .install_package_code_files(".", instdir) :
  files in 'Collate' field missing from 'C:/Users/Luedeke/AppData/Local/Temp/Rtmpygkd1x/devtools7cc4f426412/ggthemr-master/R':
  print.R
  ERROR: unable to collate and parse R files for package 'ggthemr'
• removing 'C:/Users/Luedeke/Documents/R/win-library/3.1/ggthemr'
  Error: Command failed (1)

I'm using R 3.1.1 on Win 7, latest RStudio and devtools-package.

sessionInfo()
R version 3.1.1 (2014-07-10)
Platform: i386-w64-mingw32/i386 (32-bit)

locale:
[1] LC_COLLATE=German_Germany.1252 LC_CTYPE=German_Germany.1252
[3] LC_MONETARY=German_Germany.1252 LC_NUMERIC=C
[5] LC_TIME=German_Germany.1252

attached base packages:
[1] stats graphics grDevices utils datasets methods base

other attached packages:
[1] sjPlot_1.4.4

loaded via a namespace (and not attached):
[1] car_2.0-21 cluster_1.15.2 coin_1.0-23 colorspace_1.2-4
[5] devtools_1.5 digest_0.6.4 evaluate_0.5.5 foreign_0.8-61
[9] ggplot2_1.0.0 grid_3.1.1 gtable_0.1.2 httr_0.4
[13] lattice_0.20-29 lmtest_0.9-33 lsmeans_2.11 MASS_7.3-33
[17] Matrix_1.1-4 memoise_0.2.1 modeltools_0.2-21 multcomp_1.3-6
[21] munsell_0.4.2 mvtnorm_1.0-0 nnet_7.3-8 parallel_3.1.1
[25] plyr_1.8.1 proto_0.3-10 psych_1.4.8.11 Rcpp_0.11.2
[29] RCurl_1.95-4.3 reshape2_1.4 sandwich_2.3-1 scales_0.2.4
[33] splines_3.1.1 stats4_3.1.1 stringr_0.6.2 survival_2.37-7
[37] TH.data_1.0-3 tools_3.1.1 whisker_0.3-2 zoo_1.7-11

[cttobin]

I removed the print.ggthemr() method last night. Seems I broke something in the process. Getting the same error myself when I install from another computer. I'll look into this and post a response when it's solved.