A couple of month ago this was posted by another member/LR user:
I'm running Lightroom 2.3 on a WinXP system. I'm trying to use the library filter mechanism to display a subset of images based upon the values of some custom metadata fields.
All of the values for a given field are correctly displayed in the filter's drop-down list, but if I select one that contains embedded blanks, I'll get an empty set ("No photos in selected folder"). Take a look at the attached "embedded_blanks" screen shot. I should see one image, but instead don't see any. (BTW, an embedded underscore ['_'] will cause the same behavior, so there are probably other characters as well.)
There are also problems if I select the "No Value" option (which should show be the items for which the metadata hasn't been set). The attached "no_value" screen shot shows an example of this. Instead of showing 1 image, Lightroom is showing 4 -- all of the ones that do have a value!
Has anyone seen this before? I don't know where to check to see if this is a known problem.
One of the answers from a community expert confirmed it was a known problem, but not widely known. I have thus far installed v2.5 and this is still not working as it should - pretty much the same problem as above. I have created (and filled) certain thematic custom metadata fields specifically so I would be able to use them for the filter bar/Smart Collections and of course am a bit disappointed. The good news is that my limited testing shows that v3b has indeed corrected this issue YEAH!
In the meantime, does anyone know if this was corrected in v2.6? It appears from the release notes that this as for camera updates only so I was not planning on installing unless somehow this problem was addressed.
I don't think so. But it does appear to be fixed in the LR3Beta as you say.