I have created a custom preset in the Helix II template (preset4) and made changes to the template.css file located at templates/shaper_helix_ii/css. My custom preset works and so do the the changes I made to the template.css file. But every time I click the save button in the Template Manager, and whenever I purge the cache, the template.css file and the custom preset css file get overwritten/reset to the original template.css file (which shouldn't exist anymore) and the preset css is overwritten with "preset1.css."
To clarify further, the file "preset4.css" still exists but it's contents are overwritten to be identical to those of "preset1.css" and all my changes are gone. And again, the file "template.css" still exists but all my changes are gone and the contents of the file have reverted back their original state.
This forces me to keep a backup of both template.css and preset4.css and upload them to their appropriate locations whenever I make a change in the Template Manager or purge the cache.
What can I do to avoid this problem?