I forgot to check this myself a few months ago when I used the trial version of Lightroom 5. And this problem may affect only Windows PCs, so if you're using Mac you may not have experienced it. If you're not already familiar with the problem, it's described here: "Display 'flashes', edits lost". Basically, with LR4 (and possibly earlier), an odd problem occurs when going through Lightroom to apply additional edits in Nik, DxO FilmPack, Perfect Effects, etc. After the edits are applied and you're returned to Lightroom, the newly edited files (JPEG, TIFF, whatever) behave oddly. After every additional edit choice (for example, tweaking color, sharpness, anything at all), the photo will blink or flash, causing a delay of a few seconds after every editing tool adjustment. It's annoying, especially when finessing subtle additional adjustments. So far the only effective "fix" has been to exit and restart Lightroom. Adjusting the autowrite to XMP options hasn't helped. It isn't a matter of syncing the folder either. I've tried one way with my desktop PC and another with the laptop, both running LR4. Same problem every time. I do most editing in Lightroom so it's only an occasional annoyance, but it's enough to keep me from buying Nik. My versions of DxO FilmPack3 and Perfect Effects 8 are freebies so I'm not too annoyed by the blinkies+restart Lightroom "fix". But I would be annoyed if I'd purchased Nik and realized this problem continues with LR5. Apparently it's not the fault of the external editors, and I'm not sure whether Adobe has ever issued an official fix for this problem.