On a system that already has an installed beta1 of LO, I installed the beta2 without uninstalling.
After that there is one LO on the system but double entries in the system mangagement under "software"
That is because the beta1 build had a bug: it identified itself using the same codes as OpenOffice.org (so it replaced an already installed OOo, which was not the intention). In the beta2 build this has been fixed, it is now a totally separate product, and can be installed at the same time as OpenOffice.org. This then has the consequence that one can also install beta1 and beta2 at the same time, even if that obviously doesn't make any sense.
So, just uninstall the beta1. Whether that will disturb the beta2 I don't know, but if it does, uninstall it, too, and reinstall it once more. Resolving as WONTFIX as this is just an unavoidable consequence of an earlier bug that now has been fixed.
(So yeah, it might have been possible to avoid the problem described here by using some detailled logic in a custom action in the installer to find out if there is an OpenOffice.org or beta1 installed (remember, they use the same product code), and in that do further checks to find out which one it in fact is, and if beta1, uninstall it. But developing such a custom action could well have taken a week, and it was better to get the beta2 out quickly than to let the beta1 be available any longer.)
Does not happen with actual versions. Closing.