I can’t find a blue keycard in the Scientist’s house – I’ve seen the Rupee-device (it’s high on the right side), but can’t get to it. Also, I’ve seen a cherry on the top floor. I’ve seen another cherry in Marsh Zone (I think) , but can’t get it either.

A little help?

At the scientists house there's actually a secret area that you need to blow open in order to get the blue keycard.

And if you can take a pic of which cherry in the marsh I could tell you how to get it