A couple of points to make, if I might.
The original Klear was just that - clear. The 'second generation' Klear is the Pledge version that has a milky appearance but dries transparent. It had to be changed, supposedly, because small children thought the clear product was something to drink.
The original stuff started to disappear about three years ago. It had been withdrawn, but you could still find shops that had stocks, and as it lasts for ages, no one worried too much, but then the stocks dwindled and suddenly a big debate about what works and what doesn't, by way of a replacement.
It can still be found on E-bay for something like £25! The last bottle I had was two years ago, at a model show a guy had a bottle under his table for £3. I still have it, well, part of it.
The solution is to find a product that is what the original was, a clear acrylic floor sealer. Actually, you'd be surprised at how many products are out there that fit the bill. I use a product I found in my local store, £10 for a litre, and it works fine.
About spraying it, it's an odd liquid. It's thin, yet it's not, because of the acrylic polymer base. If you spray it 15-20psi it tracks with a slightly bumpy look on the surface because it needs more pressure than that, but if you rack it up to 25-30psi it sprays much better but creates a dangerous (to you) air fog, so you must wear a proper respirator, not just a dust-mask sort of thing.
Also, if spraying, spray it about 6-8 inches (say, 20mm) from the surface, at right angles to the surface, to avoid laying on too much at an 'off' angle. It should be sprayed when the air isn't too cold or humid, as the humidity will trap in the liquid and it will go flat.
By the way, Alclad do a range of similar products now, from gloss to matte, so don't panic if you can't locate Klear, whether original or Pledge.
