The drainage channel is fine, I poured a jug of water in and saw water coming out 3 holes on the outside, so in theory if the innermost channel fills up, it should spill over into the drainage channel and drain away, but as you said (and I love the word you used to describe the effect) it is...
Hi all! Long term lurker, first time poster here - been using DIYnot forums for many years and always managed to find an answer, alas this one has me stumped so time to create an account and get posting!
We have some bifold doors in our kitchen that occassionaly leak in a very specific place...