I have had two litter trays in there, one is the fine Catsan clumping and one was the Oko Best clumping litter. But that is quite coarse and she didn't even go in that one so I took it out. The Oko Best was a covered tray as I thought if she was missing the tray the lid would stop that, but maybe she didn't like the lid. I will put back another tray with a new litter and without a cover to see if that helps.
She has weed and pooed in the litter tray a number of times, just not particularly regularly.
My boys are not nearly as fussy - they will go in together and do their business, or go while I am still cleaning the tray! But she is a girl and I'm pretty fussy about toilets too!