Conservatory panel seal leaking

I've been chasing leaks in this conservatory for about a year and a half. Whenever it rains, small puddles form on the floor, right along the baseboard trim. The base of the wall on the outside has a flat ledge along the bottom that tends to accumulate water against the wall, instead of encouraging it to drain away. So I stripped all the old caulking out of that outside corner and carefully laid a new bead to seal it up.

It didn't help at all. So we did some tests with the gentle spray of a hose and my wife keeping watch inside, and we found that the panel itself seems to be leaking. When I drip water against that black gasket between the panel and the frame opening, it ends up inside on the floor.

Any suggestions on how to fix this? I would replace that gasket, but I can't figure out who made the panels or where to find a replacement. Anyone know how this panel goes together? The inside looks much the same, with a similar gasket. Doesn't look like I can pop the panel out toward the inside... is it sandwiched in the frame somehow?

I could slather a bead of caulk over the joint on the outside, but it's going to look pretty ugly.

Any ideas would be much appreciated.

Thanks,

Dave

I see what you mean... It's the black seal that has a gap at the end of the vertical piece.

Rubber silicone sealant maybe? Masking tape and and a wet rag?

Your drainage holes have been blocked, The silicone line between the bottom of the frame and the cill should not be there. This is where any water that gets past the gaskets is ment to get out.