require(ggplot2); require(dplyr); require(lubridate)

Introduction

directory<-paste0(getwd(),("/folder1"))
tmp=list.files(path="folder1")
files<-as.vector(sapply(tmp, function(x) paste0(getwd(),("/folder1/"),x)))
temp_df <- read.table(files[1],fill=TRUE,header=TRUE,sep=",",quote="")[0,]
tnames<-colnames(temp_df)
for (i in 1:length(files)){
  currentFile<-read.table(files[i],fill=TRUE,header=TRUE,sep=",",quote="")
  # print(dim(currentFile))
  if(nrow(currentFile)>0){
    temp_df<-rbind(temp_df,currentFile)
  }
}
tbl_df(temp_df)
## Source: local data frame [4,211 x 12]
## 
##                     folderFileId
##                           (fctr)
## 1  0B6yMZ7pqUvCPTUpDZFpGaWFVWWc 
## 2  0B6yMZ7pqUvCPTUpDZFpGaWFVWWc 
## 3  0B6yMZ7pqUvCPTUpDZFpGaWFVWWc 
## 4  0B6yMZ7pqUvCPTUpDZFpGaWFVWWc 
## 5  0B6yMZ7pqUvCPTUpDZFpGaWFVWWc 
## 6  0B6yMZ7pqUvCPTUpDZFpGaWFVWWc 
## 7  0B6yMZ7pqUvCPTUpDZFpGaWFVWWc 
## 8  0B6yMZ7pqUvCPTUpDZFpGaWFVWWc 
## 9  0B6yMZ7pqUvCPTUpDZFpGaWFVWWc 
## 10 0B6yMZ7pqUvCPTUpDZFpGaWFVWWc 
## ..                           ...
## Variables not shown: fileId (fctr), fileName (fctr), mimeType (fctr),
##   createdTime (fctr), modifiedTime (fctr), owners (fctr), revisionId
##   (fctr), lastModName (fctr), lastModEmail (fctr), X (fctr), X.1 (fctr)
temp_df<-mutate(temp_df,createdTime=ymd_hms(createdTime))

# created_df<-group_by(temp_df,month(temp_df$createdTime,label=T))
created_df<-group_by(filter(temp_df,mimeType!="image/jpeg"),month(temp_df$createdTime,label=T))

daycount<-summarize(created_df<-group_by(temp_df,day=date(temp_df$createdTime)),count=n()) #por día
g<-ggplot(daycount,aes(day,count))
g+geom_line(stat="identity",aes(color=count))

usercount<-arrange(summarize(created_df<-group_by(temp_df,lastModName),count=n()),desc(count))

usercount2<-mutate(usercount,percentage=count/sum(count))
usercount2
## Source: local data frame [144 x 3]
## 
##                              lastModName count percentage
##                                   (fctr) (int)      (dbl)
## 1                           Beno Juarez    710 0.16860603
## 2                          Montse Ciges    549 0.13037283
## 3                         Angelo López    507 0.12039896
## 4           Maria Gabriela Garcia Lopez    309 0.07337924
## 5                      Norella Coronell    291 0.06910473
## 6                         Cynthia Polar    233 0.05533128
## 7          LORENA CAMILLE ARENAS LOVERA    168 0.03989551
## 8                                          154 0.03657089
## 9   DANIELA VIRGINIA QUEQUEZANA VIDALON    128 0.03039658
## 10        KARINA NICOLLE ASTUCURI SAENZ     98 0.02327238
## ..                                   ...   ...        ...
h<-ggplot(usercount2[1:30,],aes(reorder(lastModName,-count),count))
h+geom_bar(stat="identity")+theme(axis.text.x = element_text(angle = 90, hjust = 1))+aes(fill=count)

Graph only shows the 25 most engaged authors.