Why is there nog circuit information on the microlight strip Middenmeer (The netherlands)

Likely because there is no official visual approach chart (it not being an ICAO airfield with a published chart in the AIP). For private strips, we depict the circuit if the airfield owner/operator sends us the relevant information. It looks like you've found some there - if you tell us where to find updated information, I'll ask my colleague to look at it.

https://www.vliegveldmiddenmeer.nl/homepage/voor-piloten/procedures

Thanks, I think we've managed to get this added for this week's chart update.