I report it (0.99e) works correctly on Slackware Linux 14.2 (i386)
I do have a few remarks, beginning with one tiny bug: Selecting "stable" for Lazarus fetches 1.6.0, not 1.6.2.
Other stuff is mostly wishlist suggestions. First, I'd like to have a Stop button; there is no way to stop the process once it begins, so in case I notice I've made a mistake, the only way to stop is to close the app... and it isn't so easy here on Linux - I had to terminate it from a task manager...
The other thing... when I had some errors with svn download of Lazarus, the process failed and I had to try again, and I had to wait for fpc to be cleaned and rebuilt all again. When I had several download failures (I had some network problems with the computer), I had to wait for several clean-compile cycles until all Lazarus files were correctly downloaded, so it took quite a while. I'd suggest an option to install/update Lazarus only; possibly with a check for working fpc first, but I don't think it would be an issue because if build fails one could easily start a full install. Another option may be to just download source without building; I solved my problem by manually svn-updating the directory, perhaps this could be made automated from the app.
But, like I said, this is mostly my wishlist... the program is great even as it is.
Big thanks!