At 44:04 in The Silkworm: Part 1, the distinctive burgundy and yellow cover of the UK hardback of Harry Potter and the Order of the Phoenix is visible in Daniel Chard's bookshelves. J.K. Rowling wrote both the Harry Potter and Cormoran Strike series.
When we are first introduced to Daniel Chard (Tim McInnerny), the published screenplay for Fantastic Beasts and Where to Find Them (2016) can be seen on a bookshelf in his office. The screenplay/book was written by J.K. Rowling, who also wrote (under the pen name Robert Galbraith) the original Cormoran Strike novels that this series is based on. Rowling also serves as an executive producer for the series.
The Talgarth Road property depicted is one of the very distinctive "St Paul's Studios" designed by Frederick Wheeler and built in 1891 for 'bachelor artists'. These have huge arched windows of a very original design, which face the street, to make a very light area for artists to work.
Robin erroneously goes to King's Cross station to catch her train to Manchester. She should have gone to Euston Station, half a mile away.
When returning from Chard's place in Devon, after their roadside café break, Robin chooses to drive a very unusual route to London, via a single lane country track, and has to divert across fields when this is blocked. They have made an illogical error by placing that scene after the one in the café.