Original versions of the software were written in .NET and were windows only. Back then we used windows serialization to save .logicdata files. Since then we have moved to cross-platform software using Boost for serialization. These two serializations are not compatible and require different versions of the software to open. Unfortunately there is no way to convert from one version to the other making older versions impossible to open in the new versions of the software.
To open any save files saved with version v1.0.34 or older, you can still open the files with an older version of the software. Below are links to an older version of the software that should open them just fine.
Please note that this software was last released in late 2010, and should not be confused with the new software versioning, which started with 1.1.0. All software releases in the range 1.0.x were windows only, and all releases 1.1.x where cross platform.
trello ID: 57215d735c097e59d3d1fe84