In a multi disk hardware installation, particularly with other previously installed operating systems, the partitioner included with the Mageia 5 installer can behave unpredictably. This is now a known problem but was identified too late to be fixed in the general release of Mageia 5.
Worse than the problem itself is the decision to finish the new release with this bug. Yes, there is a workaround available, but whom do we want to attract with such complicated things? Newcomers who would like to try Mageia for the first time? With no possibility left to offer an easy installation for less experienced people? Unlikely. Advanced users with more complicated hardware setups? I don't think so. Problems during installation may arise if you have more than one drive or multiple partitions or a software RAID or already an installed OS or personal data. Well, how often does it happen that someone wants to install Mageia on a completely new computer system with only a single empty drive?
I am afraid that Mageia will lose its very good reputation once the first official reports of data loss and nonfunctional installations are available. I think it is better to postpone the final release another couple of weeks than to provide this kind of ”in-time killer application”. There are not many things which could be worse for the whole Mageia project.