Bugfix: version 1.0.5

Fixed a few bugs:

• Sometimes, when loading a new simulation, it would go bananas due to synchronization issues: the new particles would use the old simulation’s settings
• Some presets were saved using a slightly broken version of the simulator, with erroneous values in the rendering settings that lead to confusing options in the rendering settings which would crash if selected
• Loading & saving didn’t remember the last directory they were opened in and the path to the currently opened simulation

Enjoy!