Yes new shares are going to be issued this round.
The calculator has used Chip’s pre-money valuation which is £86,786,000 based upon the total shares + options in the company multiplied by the new share price of 1.409016. Your current share percentage figure comes from your holding over total shares + options currently. The percentage figure if you don’t invest comes from your holding divided by total shares + options + new shares to be issued.
The pre-emption figure to avoid dilution comes from multiplying your current holding percentage by the total new shares to be issued, then multiplying this by the new share price of 1.409016 will give you this pre-emption amount.
Hope this answers your question.