Hmm tried to run the latest version (3.4) on Linux, but get a core dump if I create a new demo session on Poloniex (as I'm still evaluating the product) with the following currency pair: ETH/BTC, BTC/USDT, ETH/USDT. Rest is default (0.5 BTC on start). However, if I start the demo session without changing anything (i.e. default currency pairs), it starts normally. This behavior didn't happen on 3.3. I also made sure I deleted ~/.leonardo as I though perhaps old settings might be conflicting, but didn't help. Running Ubuntu 17.04 x64 fully updated.

dbolivar@xxx:~/leonArdo-linux$ ./run-leonArdo.sh
./run-leonArdo.sh: line 13: 23462 Aborted                 (core dumped) QT_PLUGIN_PATH=$DIR/plugins ./leonArdo

EDIT: even when the interface loads, it crashes after a few seconds with the same core dump message above.