Wait for a fully working Florence in Wheezy or backports
0.6.0-2~bpo70+1 is affected by http://bugs.debian.org/628124, and 0.5.1-1 from Wheezy is affected by http://bugs.debian.org/704962. Hopefully one of these is brought to fully-working state at some point.
Parent Task: #6015 (closed)
To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information