Files that cannot be read by a CSV reader should be deleted immediately to avoid that potentially malicious resources are hosted on this public server. A simple check for file extension is not enough. Arbitrary files can be uploaded by just adding the extension *.csv.

Flags to check whether the "Next" button has being activated have been added. Needs to be adapted due to a bug:

This notification can be omitted, since there is already a "generating report" notification on the background.

Known issue: https://github.com/rstudio/rstudio/issues/4718

Another solution is to use a numeric input field that does not accept other characters.

Consensus explanations to be updated after input request.

Whitespaces should be trimmed here as well, e.g. if a space character is entered and report generated, this error also occurs.

Same for "Introduce the number of samples and click >>".

In my opinion, this sentence can be removed in general. At this stage the user should already know how to navigate. It does not add any valuable information.