Anybody tell me how I can remove and check my toilet, as I appear to have a slight leak (signs of pink toilet fluid on toilet floor) and hand pump seems to have lost a lot of power) perhaps plunger seal leaking?.
You can't remove the whole thing; well you can but you wouldn't want to.
The leak is more than likely going to be a loose or split pipe, which you might find via the cassette compartment as Birdman suggests.
As for the loss of pump, this will almost undoubtedly be down to a broken Pump Retainer. Check item 26a which is illustrated and marked in the exploded drawing, you can find by clicking here. This part is readily available from most decent accessory stores with a Thetford parts rack. There's a leaflet showing access to the manual pump, available at this link.
If you're up for it, the existing retainer can sometimes be repaired, but the part is only £6-8.