[Tails-testers] FAT32 external drive corrupted

Hy,
I'm a proud user of your system.
Because of it, I wanted to be usefull and belong to the testers.
I've tried 2.0~rc1 ...
But it seems that it completely fu**ed-up my FAT32 external precious personal hard-drive ! !
Is there an known issue ??
For the health of my hart, a quick answer would be appreciate. Even a partial answer.
Thanks for your work,
ntf