Why can't I install CMSclassifier?

[Qing123456-luo]

I have tried a lot of times, and every time I got the folowing error:
#############

install_github("Sage-Bionetworks/CMSclassifier")
Downloading GitHub repo Sage-Bionetworks/CMSclassifier@HEAD
WARNING: Rtools is required to build R packages, but is not currently installed.

Please download and install Rtools custom from https://cran.r-project.org/bin/windows/Rtools/.
√ checking for file 'C:\Users\Luoqq3\AppData\Local\Temp\Rtmp2xOSCV\remotes1ea822ef7f21\Sage-Bionetworks-CMSclassifier-ba02ec5/DESCRIPTION' (500ms)

• preparing 'CMSclassifier':
  √ checking DESCRIPTION meta-information ...
• checking for LF line-endings in source and make files and shell scripts
• checking for empty or unneeded directories
• building 'CMSclassifier_1.0.0.tar.gz'

• installing source package 'CMSclassifier' ...
  ** using staged installation
  ** R
  ** data
  *** moving datasets to lazyload DB
  ** byte-compile and prepare package for lazy loading
  错误: (由警告转换成)程辑包'randomForest'是用R版本4.0.2 来建造的
  停止执行
  ERROR: lazy loading failed for package 'CMSclassifier'
• removing 'D:/R language/R/R-4.0.0/library/CMSclassifier'
  错误: Failed to install 'CMSclassifier' from GitHub:
  (由警告转换成)installation of package ‘C:/Users/Luoqq3/AppData/Local/Temp/Rtmp2xOSCV/file1ea86a6a4406/CMSclassifier_1.0.0.tar.gz’ had non-zero exit status
  #############
  I don't know what's wrong.
  Could anyone help me?

[cloudbroken]

I don't think anyone is maintaining this package, so you may not get much help here.
The CMSclassifier package is actually pretty simple, it is a few functions and some data. You might have more luck if you look at the R code and just run the functions yourself.