All symptoms point towards a blocked drainage channel. Often, the rubber seal that runs around the edge of the door frame can look perfectly fine and appear to be free of tears/snags, etc. It's the channels underneath them that get blocked by decaying leaves and the like. If you lift up the rubber seal and locate one of the drainage holes (there will be several of them at intervals along the frame), place an airline over the top of it and blast pressurised air through, it will normally clear any blockage.
If that doesn't work it will either be the seal itself that is damaged or has become dislodged, in which case it will need replacing or refitting; or there could be a problem with one of the doors, which can be bent out of position quite easily by something as simple as a strong gust of wind catching it whilst it's open.
There is one more possibility, and that's a leak in the heater matrix. It's a bit of a Rover bug bear, unfortunately, but it's much more common in the Freelanders, Discoverys and RRs so I'd check the seals, drainage channels and doors first. If it is the heater matrix you'll normally find that the water enters around the footwell.
I hope this helps, and I hope you get to the bottom of your problem!