Thank-you for your inquiry with regard to the ruler legend box. Sorry you have encountered some difficulties.
You are correct in your observations, this however will be fixed. It has been reported to our software development team and will be corrected in due course.
We are continuously improving the abilities of PicoScope 6 and will ensure this is fixed as soon as possible.
In the mean time if you require further assistance please do not hesitate to contact me via firstname.lastname@example.org