If it's only one short wall, remove the baseboard and shim it outwards a bit, then disguise the gap at the top with some backing and caulk. It will give you enough room to cover the gap at the bottom with the 1/4 round. Did you do a full glue application, or only a perimeter glue? For situations like this, I find that perimeter glue isn't enough over time. You get some creep, even though the manufacturer says you won't. That is what ends up affecting the join areas. With the subtle height difference that you have, I'd expect the area to only telegraph that worse when the inevitable creep happens. You might think about a marble threshold there. It would be traditional for an older home, and eliminate a lot of your now and future problems.

Glennsfc, you are correct about doing all the research before buying a floor. I had read all the reviews and I knew I was taking a chance on this flooring. I was hoping I would be one of the lucky ones who wouldn't have any problems. And I am happy with it for the reasons I stated. I just wish it had been more durable. And Duraceramic is more expensive than most tile, but costs less to install. Overall, it costs about the same as tile. And doug_gb, yes, tile and wood are ABSOLUTELY better products. But no matter how much poly you apply to wood, it will warp if you have enough standing water. It's not exactly the best product to use in a kitchen, although many people do and probably don't have any issues with it. And tile is hard. If I stand on it for too long, for even an hour or so, my back and legs ache. I can stand on my duraceramic floor while cooking and doing dishes and not have a problem. And tile IS cold. I have tile on my floor around my fireplace. It's right next to the duraceramic. The tile is cold to the touch while the duraceramic feels the same temperature as the room. I wish I had a way to test the actual temperature difference, but the tile IS definitely colder. (And I have tile that is farther away from the fireplace that is still cold, while the duraceramic next to the fireplace still feels like room temp. So, it doesn't have anything to do with distance to the fireplace. It is the tile.) But we are planning on redoing our master bathroom soon, and we'll probably have to replace the vinyl floor with tile, just for resale value. And odds are I will put in tile when we have to replace the duraceramic. And then I'll be over in the tile forums complaining about how much colder my house is and how my back and legs always hurt... I just don't think you can find perfection in a flooring product. You've just got to look for what's most important to you. So, I wanted to let people know that there are good things about duraceramic, but that the tradeoff (durability) just might not be worth it to them.

Your polystyrene manufacture will have tapes that can be applied at seams for the best results. Not sure why you are trying to 'seal' the seams....air or water intrusion? Are these walkout basement walls or fully below grade? Shouldn't much matter anyhow since it is required by the manufacturer and building codes to cover the polystyrene with at least 1/2" drywall for fire and smoke prevention reasons...

Thanks for your help, Johnson Flooring Co.. I guess there are different types of "sealers" as I don't remember any "dissolving" of the two edges, the first time around by the installers (I didn't look with a magnifying glass though), it was more of a line of clear sealing stuff that looked like a bubble (like crafter's bubble paint or 3 dimensional paint from a squeeze bottle) across the seam, that dried flat. Softening the vinyl first sounds like a great idea except that I wouldn't know what temp to use without burning it. I was going to just use heavy cinder blocks and flatten it out first. I live in a pretty humid environment (cookies, crackers get softer over time instead of getting stale and hard), so the vinyl is kinda soft already. Another dilemma is the edge of the part that's lifted up is discolored brown (it's a beige floor, with beige "fake" grout) so I don't know what to do about that except try to shave away the discoloration with a razor blade without causing it to lift up more and then do the glue. What tape do you use that sticks to the floor but not the glue and then later is able to be removed? After gluing it, I was just going to cover it with wax paper or parchment (has silicone) and then a cinder block or two for a few days and then remove the paper and do the sealer stuff.