rPlot won't show in Shiny app

Question

I have a app, where I want to use rCharts and polycharts, to create a plot with a tooltip. But the plot doesn't show up, when I load the shiny app, and I can't figure out why.

Here is my ui.R:

library(shiny)
require(rCharts)

shinyUI(fluidPage(
  titlePanel("Please work..."),

  sidebarLayout(
    sidebarPanel( "Test:",
              uiOutput("TestSelection")),
    mainPanel("Plots (show me the money, please!):",
              showOutput("tempplot","polycharts")
              )
  )
))

And here's my server.R:

library(shiny)
require(rCharts)

#Test of rcharts and shiny.

df1 <- read.csv("//KED-FILE/ASIC-Shared/users/jhertel/Work/R_workspace/oban_test_data.csv",quote="")

shinyServer(function(input, output, session){

  output$TestSelection <- renderUI({
    df <- df1
    selectInput("TestSel", "Test Variable", ls(df, pattern = ".*?_meas|.*?_calc"))
  }) 

  output$tempplot <- renderChart2({
    dataPlot <- df1[,c("DUT", input$TestSel, "Temperature")]

    r1 <- rPlot(input$TestSel ~ Temperature,
                data = dataPlot, 
                type = "point", 
                tooltip = "#!function(item){return item.DUT}!#", 
                sample = FALSE)

    r1$guides(
      x = list(
        min = pretty( dataPlot$Temperature ) [1],
        max = tail( pretty( dataPlot$Temperature ), 1 ),
        numticks = length( pretty( dataPlot$Temperature ) ),
        labels = pretty( dataPlot$Temperature )
      ),
      y = list(
        min = pretty( dataPlot[, input$TestSel] ) [1],
        max = tail( pretty( dataPlot[, input$TestSel] ), 1 )
      )
    )

    return(r1)
  })
})

I've tried different things, such as options(RCHART_LIB = 'polycharts'), using as.formula around input$TestSel ~ Temperature, adding a reactive element on the TestSelection-ui, I've tried changing browser, from internal, to Firefox, to Chrome.

I am suspecting the input$TestSel ~ Temperature to be the reason, as when I inspect the javascript with Chrome, it doesn't look like input$TestSel has been interpreted to the desired value. But I am a total noob to javascript, so I wouldn't know. EDIT: I am fairly certain that my error occurs here, as setting the changing input$TestSel to a desired value results in the desired plot... Still don't know how to solve it, though.

When just using R the plot shows up as desired in the viewer.