save file getting corrupted uppon saving

[NicolasGE]

here are the files:1=original.5=saved.zip

steps to reproduce:

1. i opened my save file with the editor
2. i saved the file with the editor

expected result: nothing is changed

actual result: a ~2kb file is created, instead of the original ~700kb, and it no longer works

notes: i think this might be caused by some strange custom items i have from way back, since it doesn't crash/corrupt my recently made Mose .sav

Example of a strange custom item

[NicolasGE]

this is a similar issue to #23 and #20, i think they're all somewhat related, but they might not be, i can't be sure since i only tinker with stuff like this