I compiled and installed both Qt and XForm version of LyX 1.3.0 a few weeks ago.
Qt version is really pleasing to use and the viisual comfort with aa fonts is great. I do have 2 small concerns. 1. There are some not translated options in the different combo boxes (I use it in french) -- if I note the different missing sentences, who must be advised? This problem occurs in both version (Qt and XForm). 2. Only in Qt version: you can't do a vertical space fill for a paragraph, it doesn't work. Selecting « ressort vertical » (vertical fill I guess in the english text) does nothing. The other options work. I had to use \vspace{\fill} in ERT to get my paragraph pushed at the bottom of the page. R. Ouellette