Hello folks, nice work on this project !
I'm encountering a bug using this input SMILES : CC/C=C\C/C=C\C/C=C\C/C=C\C/C=C\C/C=C\CCCCC(=O)S

The correct molecule is, as drawn by MarvinJS :

The cycle should not be there, I believe that it's because the software tries to avoid a collision between the two ends of the molecule.
Steps to reproduce
svg_from_smiles('CC/C=C\C/C=C\C/C=C\C/C=C\C/C=C\C/C=C\CCCCC(=O)S', 'output.svg')