I have been reading the thread on the BLFS Support mailing list regarding gtk-1.2.10 and gtk2 it looked like. Was this you? GTK1 and GTK2 are different and were designed to run side by side, but 1.2.10 and 1.2.9 are from the same development arm (GTK1) and so I don't really know if they can be run over the top of each other - but correct me if I'm wrong!
As far as lock ups go the way you can really solve problem is by working out what you have to do to lock it up - i.e is it repeatable everytime? Check the logs in /var/logs to see if anything is not right with something, although with a lock up I doubt you will find much.
Apart from that, drastically you could re-install LFS. Although this is a drastic measure at the moment it is something that can happen with LFS.
BTW - if your looking for a file manager try gentoo (not the distro!) It is easy to install, lightweight and very functional.